Rhino's rush--double damage is never a good idea
I don't think it's that bad. Paladins should have more options to be nasty at charging. Barbarians and Tome of Battle classes just blow them out of the water in that area. Heck, wildshaping druids, too.
Find the gap--nothing should ever make melee attacks into touch attacks. It is very bad juju when you can power attack for max, smite evil and spirited charge/rhino's rush. Level 12 characters end up dealing near 100 points of damage per hit and only missing on a 1.
Again, not that bad, and no where near as bad as Wraithstrike. It's level 3 or 4, and a Pal/Raner/Asn spell only, so it's not even available till late game. Takes a standard to cast, and only lasts round/level, benefitting one attack per round. I think in general classes like these (and Hexblade, etc...) should have better spells. And as I noted before, Tome of Battle classes, STILL put these classes to shame. Maybe you don't use ToB, and that's part of our divide in opinion. Because by level 12, they can do that kind of damage in one attack, too. As can a druid wildshaped as a large cat. As can a barbarian built right.
And there are other ways to do melee touch attacks. ToB has Emerald Razor maneuver, available at ECL 3. Standard action, one attack against touch AC. It's useful, but not broken, and gets overshadowed for damage by later strike maneuvers IME. MIC has the heartseeker amulet to get a single attack against touch AC, and the impaling weapon enhancement, a +1 bonus. Both swift to activate and 3/day. The amulet is probably broken, the weapon property might also be, but is more limited in what it can be applied ot and ultimately will cost a lot more. I'm sure there's more ways out there, these (and Wraithstrike) are just the ones I can think of right now. Of all the possibilities, though, Find the Gap is by far the weakest of such options.
Mass resist energy--If this were level 5, it might be acceptable. As a level 3 spell that nerfs any single energy encounter into oblivion, it is too much.
We put it to level 4 for arcane and divine casters. It's still very strong, and I may move it to 5th level in later campaigns. On that note, I'm not sure the Energy Immunity (or whatever the name is) spell should even exist. It does as it sounds like -- pick a type, and you're immune ot it. Lasts all day, and only level 6. I'd ban that before even nerfing Mass Energy Resist.
Delay Death--Quite simply, death from damage ceases to be a possibility after level 10 or so as long as your cleric has a minor action left. This spell changes the game in a dramatic way that is not for the better. (I recommend house-ruling the death at -10 rule to death at -(10+character level) to fix the real problem).
It still only lasts round/level, and if the target is't healed enough by the end of the duration, he's still quite screwed. I could see it in tandem with Revivify, but that'd get pricy, and is the kind of repeated abuse a DM should just say no to. Enemies, meanwhile, are free to attack other creatures. It's a level 4 spell, it will be too limited to buff the netire party with it in one combat (not to mention take several rounds to do) till near epic.
It could then cause problems, though.
Wraithstrike Nothing should ever make melee attacks into touch attacks. This is even worse than find the gap since it applies to all attacks for one round and can be trivially extended with a lesser rod of extend spell.
It's also available at ECL 3. Yeah, this one is the most ban-worthy in the whole book.
