1.Stats: Should Glalie get a stat boost, Evolution, Mega Evolution or nothing?
Glalie already has a Mega, so another Mega Evolution would be what we are discussing.
A stat boost can go to at maximum of +60 BST, but given Glalie's stat distribution, these points would be either given to Attack/Sp. Atk and Speed, or be given to all of its stats.
An Evolution is impossible, due to the fact it has a Mega, and it already has a side evolution, but it would enjoy a middle evolution.
2.Should Glalie get more abilities?
Probably, but Glalie already has three Abilities. Tough Jaws would be the most sensible one, alongside Rock Head.
3.Should Glalie get more moves?
Yes, moves like Head Smash and Psychic Fangs are a must for Glalie. Special moves such as Ominous Wind, Power Gem and Moonblast would also make it very good.
4.What additional typing Glalie can have?
Dark and Rock are the obvious ones, but Fairy, Ground and Steel can also work.