I'd like to make a case for Blaziken to receive it's HA (speed boost) as I know it has been a bone of contention for some time.
Blaziken was banned in Gen V, however the current state of Pokemmo has many more answers than Gen V did for dealing with this Pokemon.
Here are some of those answers:
5 prio moves - extreme speed, shadow sneak, sucker punch, quick attack, aqua jet
Haze
Weezing having access to Neutralizing Gas
Taunt, Trick+Choice Scarf, Lagging tail, toxic orb, Trick Room (either with or without prankster)
Jellicent and other ghosts.
Rocky Helmet, Iron Barbs
Many sub breaking tools - all the multi-hits most notably Rock Blast, the Infiltrator ability, various skills i.e Signal Beam which bypass sub.
With that in mind the impact that HA Blaziken would have on the meta-game is nowhere near as game-changing as it was in Gen V and therefore I don't believe it would have a negative impact on the game or the state of competitive play.
