Yeah, allowing Wiz Kick to be B-reversible would be great. I'm not sure why it isn't already. It would definitely help against moves like DDD's down smash which sends you off the stage and in a different direction than what you were facing.
I would argue that the new grounded Flame Choke is worse than what we have now. Since I haven't actually played the new demo yet I can't say any of this for sure, but from what I've seen in livestreams this appears to be the case.
- The hit stun looks really short. You may be able to get an up-air off on most opponents, but it looks the possibility of a trade is very high, especially against characters with good priority in their aerials.
- This change limits the kind of follow-ups that Ganon can make after a grounded Flame Choke. Currently you can follow-up with pretty much anything if you make a good read or predict how your opponent will tech. With the new trajectory though, it looks like the only possible follow-ups are uair and nair, and maybe DACUS if the knockback is just right.
- This change will actually really hurt Ganon against floaties, unless the knockback on the new version is fixed. Consider what will happen when you FC a Jigglypuff at 100%. What if she goes flying halfway across the stage? Obviously in this case there is no guaranteed follow-up, whereas with the current FC there is at least a chance.
Overall, I think that Ganon needs a move like the current Flame Choke because so many of his moves already have such high knockback. His ability to combo degrades incredibly quickly. Having a move like the current FC at least gives him the possibility of short combo strings regardless of the opponent's percent. Granted, it looks like aerial FC is unchanged, but sometimes it's easier to land the grounded one.