I'm still not sure on how using Oblivion XP instead of vanilla or, say, nGCD, compares as far as what kind of character one will end up with. Underpowered? Overpowered? (Then again, in vanilla, you could choose important skills to leave as minors and then just level the hell out of them for an artificial leg up on the competition, so maybe it all balances out.)
I think you've already got the gist of it. With OXP you won't be able to play the Minor is Major game, nor can you play the "I'll just never sleep" game, so it isn't
exploitable like vanilla, so I suppose that means you won't be "overpowered". However, unlike vanilla you'll likely find that you have much lower Minor skills than you're used to, which probably won't affect your combat effectiveness (unless you picked the wrong Majors, hehe) but can be a bit of a burden as you've already found. Setting the Preset to 0 to get "Master of All" mode might alleviate that a bit for you, if you care for it. See your .ini.
With NGCD it's a whole mixed bag simply because of the extent that you can customize it. By default, I think nGCD characters end up being a little more powerful than default OXP characters mostly because of the Minor skills,.. but I typically play nGCD such that Majors and Minors both "count" towards level equally and then adjust things so it balances out.
Anyway, you can continue playing OXP as you will and if you find that your character is too powerful or too weak, then you can change the .ini and reduce the number of skill or attributes you gain per level. You can then get OXP to let you reroll your character according to the new settings if you'd like. I think the console command for that would be "Set ObXPMain.firstTime to 0" but you should check with SF... it might 'destroy' your training sessions.
edit: nevermind the following. Restarting Oblivion fixed it, not disabling OXP.
On an unrelated note I think I found a bug... a surprising bug. My .ini is set to allow for Journeyman skills at level 3. I got to level 3 and raised my Blade to 50. The new sideways power attack works fine but now I'm completely unable to do power attacks in other directions (forwards, neutral, backwards). Switching to blunt or H2H I still have all my attacks. I've looked through OXP's scripts again and I don't see anything that would cause this but when I disabled OXP the problem went away. If anyone has any ideas that would be great

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