There were two popular models: Agat 7 and Agat 9. The second one was great machine, one of the best personal computers produced in USSR in large quantitites.
On acoustic with light or medium strings - it's OK. I used to flatten them with nail file from time to time. But it might be much easier on your finger tips just to start with electric and then progress towards acoustic.
Yes, that's what I've seen from a lot of my experiments with fine-tuning. One should be really careful to not "lobotomize" already capable model and achieve better results at the end. It's trickier than seems from multiple of tutorials.
But I believe that most of the data stored in foundation models are just useless for some particular domain. So it's better to forget something, getting really useful info instead.
Try to use less cores. RAM bandwidth is real limiting factor there, so there always some sweet spot between CPU cores and RAM bandwidth for individual system.
For example, I use only 6 cores from 10 on my M1 Pro laptop.
Both 1 and 2 versions are good enough in Russian even for some real use in production environments. But you should tolerate some crazy / weird typos and mis-wording they'll produce. Russian is complicated.
Tokens are just integer numbers, showing their position in the big vocabulary - it's that simple :)
And vocabulary is just an array / vector / list - it depends which programming language you use, each has each own terminology for that data structure.