1) Substitute
Yes, definitely. From battles that I've seen, 25 HP sub seems awfully powerful, and this seems like a good solution.
2) Field Effect Duration
Ehhhhh.... I'm gonna hold my tongue on this one, at the risk of being biased. o___o
...okay I WILL say that if these moves ARE being reduced in the amound of time they're up for, they should also have a significant energy reduction as well.
3) CounterCoat and Metal Burst
As I've said before, Counter and Mirror Coat aren't that bad with the restrictions on move substitution that we currently have, but Metal Burst should be buffed to something like 1.15x or 1x as much damage, something much lower than it currently is, yeah. Burst wouldn't be so bad if most of its good users didn't also get Taunt, making the whole Toxic thing kind of a less legitimate strategy against it LOL. (...and then, y'know, there's the fact that most users of it are also Steel-type. xP)
4) Bumping the battle cap up to 4
Definitely. Okay I forgot about the ref shortage. Let's change my vote to... errr... maybe, I guess. Dx
Other:
I really also want to see moves that are currently useless become more worthwhile. Torment is one such move. Here's the move's definition:
Torment: The Pokemon imbues dark energy into a taunt, preventing the opponent from using the same move twice in a row for six (6) actions.
Attack Power: -- | Accuracy: 100% | Energy Cost: 9 | Effect Chance: -- | Typing: Dark | Priority: 0
Hardly anyone uses moves twice in a row anyway due to the energy penalty for consecutive move use, so Torment is pretty overly-specialized if not completely worthless outright. I want to see Torment do something like this:
Torment: The Pokemon imbues dark energy into a taunt, preventing the opponent from using using the same move twice in a row or from using any moves used in the previous round for six (6) actions.
(keeps the same same energy cost, old energy cost was too much for a useless effect.)
...or something like that. The wording could be a little better, or the effect tweaked slightly, or something.
Example: Say it's a Dratini VS a Murkrow or something. In the first round, Dratini uses Ice Beam, Dragon Dance, and Dragon Rush, and Murkrow uses Torment as one of its moves. In the progressive round, Dratini cannot use any of those three moves, and cannot repeat any of the moves it uses. So basically it's like an in-game Torment that affects all the moves used in a round, instead of a single action. Same duration, same energy cost. And optionally, it could still have the same effect as the old Torment (not like it was breaking anything anyway). Maybe add something to prevent chills, I don't know. To me, this effect (or one like it) this really sort of feels closer to what Torment is supposed to do, though. I imagine this would be much more frustrating (tormenting?) for the victim, anyway.