Chase you misunderstood. I love Chestnaut and Breloom! I'm actually trying to make them work in OU to the best of my capabilities. I just disagree with the idea of another Grass/Fighting starter, especially since Gen6 already gave us one.
While Grass/Flying is more represented, all of the delegates are useless in combat, and the one that isn't, belongs to the group of legendaries, a modified one even. Who in their right mind would ever consider using Jumpluff or Tropius
The hype for an Ox starter does not reside only on the Zodiac pattern, but also includes the possibility of Tiger being used elsewhere. A perfect example would be an almost extinct Snow Leopard that resembles a tiger, or a Legendary for the SUN version. In my opinion, it's much more logical than a ... sun shark.
Bug types don't really make good starters as most pokemon games are biased against them. Remember how in the first towns you go to the people regard Bug Catchers as a lower type of trainers? Further supporting this viewpoint is the target demographic of these games, albeit altered to suit older audiences. Even if Bug/Water seems an excellent typing and GF made a huge mistake removing Water from Masquerrain, they could re-introduce it in Gen7, even if the only logical form now is... a Mosquito.
Water/Fighting appears to be the best route to follow at this point. Yes, it will sink Poliwrath further into the Abyss (or become creative and use a Belly Drum set in rain, after a Memento from Dugtrio), but it is the only starter type that never received the Fighting subtype, although chances were presented.
I could even settle for a Water/Psychic as we haven't seen those since.... (has it been that long?) GEN1