Progressing in fighting games, and I'm stuck

Hey everyone.
After a long, long period of time of not playing fighting games, I decided about three years ago or so to get back into them. I built a stick, bought a few games (SFIV, Third Strike, and a few others I can’t recall) and started practicing. I was not and still not able to devote a ton of time. Maybe a few hours every week or so.
I played, I got better and better, and as soon as I started diving into deeper mechanics, I got lost and stuck.
I have a basic understanding of the mechanics behind fighters (especially SF), I can perform most special moves for most characters I pick, I know their weaknesses and strengths, and have a middling understanding of matchups.
I’m somewhat decent at reading other players and reacting and exposing weaknesses, but about seven times out of ten I’ll get my ass handed to me.
I’ve been branching out and getting out of my comfort zone with SF and playing more Guilty Gear and KOF and beginning to understand the mechanics in those games.

The part that worries me and has made me almost give up on fighting games a few times are combos and how to defend and break out in a situation where I’m just getting hammered.
I can barely execute basic combos, let alone really complex ones. It doesn’t matter what game I play, whether it be SFV, Xrd, or P4A, I’m just bad at them. Doesn’t seem to matter how many times I practice them. I can mostly hold my own without them, but they’re not the only thing I suck at. I know I’m probably gonna just have to grind and grind some more after that to really get a grip on them, but I just never seem to make progress in that area while I get better in others.

Outside of execution, I really want to understand and dig deeper into what makes good characters good and what makes bad characters bad. I’ll have decent luck with a character, then go online to see absolutely everyone trashing that character. I guess I don’t understand how to feel out a character and understand what makes them balanced/unbalanced, low-tier/god-tier. Any tips for that?
I just feel like I’m kinda stuck at a certain level and can’t progress further. I think half the victories I take online are just sheer luck at this point. I need some sort of breakthrough and it’s just not happening. I have a really deep desire to get better at fighters, so this makes this all the more frustrating.
Anybody have any advice? Maybe some training resources I can look into?
Thank!

A huge part of doing combos is to become familiar with the situations you can land them. Once you realize when you can land them and become comfortable in setting those situations up, you’ll likely see your success rate go up.
If the problem is that you can’t actually execute the combos, even in training mode, then there’s no other answer than practicing until you can do them. However, try to diagnose why your combos drop in this case and fix those specific problems. This might involve breaking up a combo into smaller sequences, and practicing the particular part you’re struggling with until you can do that. Input display is also a must, since it lets you see how clean your inputs are.

Character strength, which is determined by how consistently a character beats other characters at the highest level of play, doesn’t matter at lower levels of play. Hell, in most games it hardly matters at intermediate levels of play. Pick someone you enjoy playing rather than what people on the internet (who mostly suck at assessing character strength in the first place) say are strong or weak.
Also, what characters do you actually play in the different games? This could be part of the issue, because different characters can have vastly different execution requirements.

I don’t think playing a few hours a week is enough. Maybe shoot for an additional 30 minutes a day of training mode time. You gotta get your combos down, as well as work on other things, like meaties.

You have a lot of learning ahead of you. Unless it comes easy to you, this isn’t a genre that you just pick up and play here and there and expect to do well online. And from what you’ve said, it doesn’t sound like it comes easy to you.

As far as training resources go, youtube has loads of guides. jmcrofts has some short, easy to digest videos. Gief’s gym is pretty popular for new players. It’s a book though(and an ebook).

This and That^

There are so many things you need to look at to find out why you aren’t doing better.

If you can land your combos consistently in the lab then you need to learn why you cant land them against a human. This will come down to how you set up the opening for the combo. You can’t just throw one out and hope it lands. To learn this quickly the best thing to do is pick on character, just choose the one you like the look of, and then watch Youtube videos dedicated to that character. Then videos of high level players using that character. This way you can skip the grinding and learn quick combos and when are good times to use them.

I say pick the character you like the look of because at the level you have indicated you are at, it doesn’t matter about tiers or any of that crap. You want to make sure you are just having as much fun as you can, because this part of your development isn’t every bodies favorite part.

I would also suggest picking just one game and one character. If you have so little time to play then you want to make sure you are focusing that time and not wasting it. After you can play one character effectively against another human it will be a lot easier to pick up another game and character.

I often spend time just doing whiff punishes and block punishes, I don’t even bother with combos and just pay attention to developing my weak points. Combos are the easiest part of the game. Learn the bare minimum with regards to frame data. Just the super basics. Don’t delve to deep until you understand it. Fighting games are based a lot on whose turn is it to attack. If it isn’t your turn, no matter what you do, you will come off second best. I feel this could be another reason why you aren’t able to do anything in a proper match.

And with regards to getting them off you. This will require correct blocking, waiting your turn, and punishing. Unless you play MKX, there is no mechanic to stop a combo in pretty much any other game. But most importantly, don’t let yourself get into that situation. Don’t blindly rush your opponent down, because if you can’t defend this is the worst thing you can do. If you are being combo’d you can’t do anything but wait.

Then practice practice practice. But practice what you are weak at.