1. Shitty music
I don't care if you love Ayumi Hamasaki, or Nightwish, or Dragonforce, or Linkin Park, or whatever the fuck raver DJs you listen to. Point is, j-pop, j-rock, cheese metal, nu metal, trance/rave etc. have been done to death in combo videos and I don't wanna hear it any more. It'd be ridiculous to expect every video to contain music I like, but Christ, at least switch it up a little.
2. Long intros
I watch a combo video to see combos, not 5 minutes of logos or whatever. This should be proportionate to the amount of actual combo time in the video, but generally I think anything over a minute is just unreasonable, and even that's pushing it.
3. Long credits
Seriously, fuck your ego. A credits list should generally be simple, nobody watching gives enough of a shit about you to warrant a flashy sequence for every single random scrub who performed a combo in your vid. Do you think anybody even watches that shit? Just scroll the names and get the fuck out.
4. Anime clips
Just... why? Why would you think anyone wants to see this shit in a combo video? It doesn't look cool, it doesn't accentuate the experience of the video in any way, all I get from it is the knowledge that you're not just a fighting game nerd but a Wapanese **** as well. Please don't do this.
5. "Flashy" editing
"Flashy" is in quotes because the only people this shit looks "flashy" to are retarded kindergarteners. You know what I'm talking about; ugly-ass glittery shit flying all over the screen, random-ass overlays (generally used to credit the combo performer - that's what the credits are for, fuckface!), added hit effects, random filters, etc. It's fucking ugly, stop doing it.
6. Stupid sound management
Whether you like in-game sound with your vids is mostly a matter of personal preference, but if you choose to enable the sound, please keep it quiet. What's the point in including music if I can barely hear it because some underpaid Japanese voice actor is spewing shitty Engrish all over it? Always disable the in-game music, if you can't, don't have in-game sound at all. You aren't fucking Timbaland, and even if you were nobody would want to hear your 'Crawling'/'Is This True Love We're Making' remix.
7. Random variations in quality/volume
This kind of encompasses a few things. What I'm talking about is changing of sound levels/resolution/quality etc. between different clips in the same video. It just looks sloppy as fuck, and it's especially annoying when I turn up my speakers for one part of a video that's really quiet just to find the next part is REALLY LOUD. Don't do it.
8. Shitty text
If you're gonna have a fucking thesis at the beginning of your vid on how Nietzsche's thoughts on Morality relate to fighting games, at least spell check your shit, Jesus Christ. Actually, it'd be nice if you just wouldn't include any kind of quote or whatever that you think sounds "deep" or "cool", because while all that pseudo-philosophical bullshit The Matrix may have blown your neanderthal mind, those of us that aren't 15 year old Tool fans just find it laughable.
Also, can you PLEASE use some fucking decent fonts? I swear I've seen videos that use Arial and Times New Roman, for fuck's sake! That looks incredibly unprofessional. Use a font, size and color that is a) easily readable when overlayed on top of the game (seriously, I think some of you guys don't even watch your videos back when it comes to this) and b) makes your video look like a fucking video, not a Microsoft Word document.
9. Too much downtime
This is pretty much annoying in the same way that long intros are annoying. I want to watch a combo video, not whatever random crap you decided to squeeze in there (usually anime clips which we already addressed but sometimes random text or whatever). I appreciate that sometimes you need a break from the action, and I do like the little skits done in-game that some people do that showcase stuff that perhaps isn't technically impressive but just looks funny, because it doesn't disrupt the flow - you're still watching a game. Another thing that annoys me is when the characters are standing around doing nothing forever before/after a combo. It may seem like nitpicking, but it's just so easy to fix. You're already editing video, why not cut some of that shit out?