I will do my best but my experience is limited with this.

1) I wasn't here last March so can't comment on that, but from late Oct-early Jan Bitcoin went up from 5k to 20k and I would assume that some of this money poured over into the altcoin scene.
2) Most probably, but nothing is guaranteed. I don't know if conditions are same as last year but the consensus between the OGs on twitter is that it will happen. I will say about December though last year the dominance had reached a peak of 60% all the way from a low 38% (when altcoin and bitcoin pumping). Currently the low this year was 33% and right now we are at 43% dominance for BTC. If we can get above 50% I think that is a positive sign for a bull run.