@Ly some of those are already mentioned (feat/savant) or blocked (kobolds), but there is also the the assumption that temporary Hit Dice can do that. Don't be a Link and invent thing or pose the rough argument of "didn't do the research"
Like Temporary Hit Points != Hit Points & Ability Damage != Damage, the extra or missing word significantly alters which rules are even being discussed. Temporary Hit Dice vs Hit Dice would be of no exception, and Epic rules uses the term Level so the question posed is Temp HD count as a level?
Now there is a lot of precedence for no and the rules don't support any argument for saying yes. Which is crippling since per Teaching the Game you must translate what you want to do into the game rules, IE prove you can is the default requirement. But to go into the concept if you houseruled it don't forget to look for collateral damage caused by the repercussions of the ruling. Like saying Bardic Music can increase your level may let you select Epic Feats, but it also means your level is higher for the purposes of determine XP. A +2 level difference is a huge 1/2 XP rate against the same CR so wanting the Feat options of say a Wizard 10 / Temp 2 means you've double the play time needed to actually be a Wizard 12.
Another thing to remember if either the group has said no Epics, that doesn't mean they've said yes to Epics and only the specifically method of progression based on XP is banned. That's actually pretty stupid and munchkin-like since you're obviously attempting to cheat and gain what's not agreed upon as not allowed.
