1.Stats: Should Granbull get a stat boost, Evolution, Mega Evolution or nothing?
Granbull has not got any boosts, but at least it can get +20 BST to match a 170 BST gap.
An evolution would make sense regardless, however.
A Mega would be a failure.
2.Should Granbull get more abilities?
Pixilate would be the obvious option if it were the case. Iron Fist and Strong Jaw would be the other options.
3.Should Granbull get more moves?
Slack Off and Drain Punch would be fun.
4.What additional typing Granbull can have?
All elemental types and Normal can work, but ignoring them Ground, Fighting, Rock and Steel can all work.