Free spells
The trouble is, her ability only triggers on the first X spell you cast each turn, and you have to do quite a lot of set up to get a properly scary discount
Vintage kept its restricted list, because some people wanted to play with powerful cards (and also because Type 1.5, aka legacy had started to take root, which, at the time, was just vintage with the restricted list renamed "banned list"), but in standard, you already couldn't play with all your cards, so there really wasn't any good reason to keep a restricted list
2: Gain control of target creature
Theyre fun enough for experienced players who just want a more casual game while still being accessible and fun for new players
3) Mana Drain Magic has come a long way since Mana Drain saw print