Yes, this! Especially now that one can have access to someone who really knows what they are doing, not only whoever is available geographically.
You are very attentive to what I have been mentioning throughout this thread; this is almost the full list of languages that I count. (I only “count” those that I brought at least to B1, as for the ones that I touched but didn’t get at least there, I don’t think it’s fair to claim them, regardless of the number of semesters spent on them — not much was retained.)
So, for the first five, it is hard to establish the actual order, as I started something and then stepped aside for years before I actually got to anything of notice. On academic CVs, I usually claim Ukrainian and Russian at “native” level fluency and English as “near-native.” Russian and Ukrainian — that’s clearly simply from the environment, but I was really lucky to start with English early and have good instruction at school, so I could study at the university where it was assumed that guest lecturers could teach in English and everybody would understand — quite a bold idea in Ukraine in the mid-2000s.
Then there were German and Polish. German is currently somewhere at B2, but pretty passive. This is probably the story of most time spent for least result, overall: I had multiple beginner teachers in secondary and high school, each year a new one, still students of education themselves, not really knowing how to do their job. So, after like 5 years at school, I could only skip the two first semesters in college, where I did another year, then multiple language classes in private language schools, on and off. I haven’t really been doing much for the past 10 years (checks the graph) — just 500 hours — so language production capabilities are very rusty, but I have an okay level of comprehension for authentic content, even scholarly sources. Before I got the job that I am starting now, I thought I would do a fellowship in Munich, so I tried to put in more effort in reviving it for a bit, but postponed that now.
Polish: I started at college, only actually ever took two or three semesters of formal instruction, then I started working with Polish literature and reading a lot, came to Warsaw to work with sources at the library, for months on end during my graduate studies (the first one, in Ukraine), some communication with the natives. Continued that during my second graduate school in the US, but it was assumed that I am coming with a sufficient level, so it was also mostly work with sources, not formal learning. I would say comprehension is at a near-native level, but production skills got very rusty, especially since my brain decided to overwrite it with Lithuanian, which I am actively trying to undo now. ~B2-C1, I would say, but with a lot of interference from Ukrainian and Lithuanian. (It’s a very inappropriate moment to discover a fun “false friend” when discussing a lease contract.)
And then I actually started counting them in order.
Sixth was Hebrew: I usually say it gets easier once you reach your sixth language. At least it’s where it got for me. Or one could say I was very lucky to have an exceptional instructor. I had no reason to start Hebrew specifically, but there were language classes that were offered at an additional cost at my university and those that were offered for free, so I roamed into the Hebrew class one year (after already having seen many language teachers who had no idea what they were doing), and then I thought to myself after a few meetings: wow, I don’t know why on earth I would need Hebrew, but I should observe him to learn how one can teach a language. I ended up marrying him. Four years in Ukraine and two intensive summer schools in Israel brought me to what they call “exemption exam,” but I wouldn’t claim that’s really the near-native level this wording might suggest. Even at my most fluent times, I still struggled with many types of authentic content, especially fast speech in videos. I started teaching a few years in, as there was a need for a teaching assistant, then on my own behalf, and also did that for a year during the US grad school, but since ~2020 I simply had to shift focus elsewhere and currently active production skills are pretty rusty.
Seventh was French, which was required at my Ukrainian grad school for a year, and then I took a few more classes in the US. ~B1 probably, I would be able to find my way in the language environment if necessary, but that’s very far from full comprehension. (One situation when it was indispensable was a trip to Tunisia, surprisingly. In France, despite the common stereotypes, people preferred using English over listening to my bad French.) Haven’t touched that for quite a while.
Eighth was Spanish — started that in the US: we planned a trip to Mexico, I duolingo’ed Spanish for a few weeks before the trip, and then I simply showed up in the third semester of Spanish after the trip. I have no idea why I would need it, honestly, as we never went on another trip to any Spanish-speaking country, but I have been doing tiny bits of it since then, just for retention and for duolingo points — Spanish course is done relatively better than, let’s say, German, and I am still at a level where I can learn new things from it. Mostly keeping at retention level. ~B1 I would say, though a bit more active for production than French. I believe that 338 hours over the past ~7 years on my goal reflect the time spent already after I finished that one college class.
Finally, the latest addition: Lithuanian, my ninth language. ~B2 over the past 27 months, as I said earlier. Of course I am very far from fluency, but I finally reached the level where natives stopped saying “well, you don’t need to be breaking your tongue…” (under which I assume they are imploring me not to maim their language) and continue in Lithuanian with me and only switch to Russian when they see my Ukrainian passport (super-logical, yeah, but I’ll leave my hypotheses on these postcolonial entanglements for a different genre).
I also touched at some point: Tatar, Turkish, ancient and modern Greek, and Yiddish. But very little is retained, regardless of the number of semesters or otherwise measured time and effort input, so it would be unfair to add them to the list. Can do a market conversation in Serbian (good afternoon, half a kilo tomatoes please, [understand the declared sum], thanks, goodbye) though never actually learned it. Because it’s Slavic, so basically comprehensible to some extent in the first place with three other Slavic languages under my hood, and because people really don’t want to use English there (unlike, e.g. [North] Macedonia). Wouldn’t be able to pull that with Hungarian or Georgian, of course.
Okay, this ended up quite an essay 
I think I announced that I would write one in one of the intro posts in this thread, over a year ago, so thanks a lot for prompting me to finally do it.
There remains a question of why, I guess. Apart from some idea of needs and opportunities and responsibility (in Lithuania, it’s possible to go without Lithuanian — people don’t expect and don’t want foreigners to use their language, but I feel like I ought to take the responsibility to learn it if I want a longer connection than this stint; in Poland, many people don’t care that you might be just passing by from a different country: on Polish soil, Polish please, or simply have no skills otherwise even if they don’t espouse that idea consciously, so I can’t imagine how I would be able to pull this through if I hadn’t already known the language, even if the job itself seemingly doesn’t require language skills). It just really scratches my brain in the right way — making connections between words and slowly unraveling how languages work, discovering influences between unrelated but historically intertwined languages, and discrepancies between genetically related ones.
), so take it with a lump of salt. But it seems to explain things I’ve seen or the fact I automatically assigned value to learning Lithuanian.