Mega Zoroark with a boost on defensive stats.
Mega Houndoom with more Defence and Speed.
Mega Masquerain, more Sp. Attack, Speed and Water Type instead of Flying Type.
Mega Slaking, just changing Truant for Thick Fat.
Honestly, Zoroark is meant to be a fast sweeper. For any who don't know meta terms, FIGURE IT OUT. It's rather self explanatory. Zoroark should focus on that, rather than turning him into a rather poor bulky pokemon. The only way to get away with that is to have a stat total at least equal to Arceus', and that's adding NOTHING to offensive stats. It's defense is too paper-thin. Unless you solely focused on one defensive stat, then it may be doable, but it's offensive potential and power is too great to waste on devensive upgrades.
As for Masquerain, like with Nincada, it should just have a new branching evolution that carries the old type. They should make a Samurai-based evo to Nincada that's Bug/Ground (because it's not Bug/Flying and it'd evolve from Nincada, an awesome Bug-type), and likewise could make a water/bug evolution based around perhaps some kind of bug-like dancer, having stronger defensive stats, as well as physical attack (I'm naming it Gerrimenco).
Houndoom would need a
much deeper defensive movepool to pull that off, because bulky and fast together on a sweeper usually doesn't work, as well as sharing the same problems with Zoroark as mentioned above.
Give Slaking Defeatist instead. That way it's not too OP.And more attack and speed/defense/sp. def. (just a bit. It needs to be able to compete, but once again, not be OP).
So, I wrote a huge article... on Pokemon... (Arceus-damn that was long) Don't hate me for going directly against your opinions, these are just
my
opinions and their only purpose is to explain what I think would work best.
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