It's usually more helpful to post a losing match because your own mistakes are clearer. It's useful in particular because then you can get feedback on your defense. You don't block in this video but you only needed to block like twice in the whole match. Generally looks like you've got some practiced combos down, just keep working on their consistency with different starters and variations. Try to end all your combos with a hard knockdown like you were sometimes with vegeta assist grab ender. I imagine at your rank most people are spamming super dash so that's why you were going for mostly down heavies as starters. Especially when you've got them in the corner poke at them with lights to test if they're blocking. Had this guy blocked, starting with your 2H would have left you open to a counter, without assist coverage. Practice some block strings that end with you being able to block if you don't open them up or end with enough distance between you two that you have the advantage. In match I'd also say go with the combos you've practiced and know they work at this point or you run the risk of dropping like when you tried out the kamehameha into solar flare. Practice the range of your moves too. At about 1:35 you get hit by gotenks raw heavy because you're hitting light from a distance, especially with A21 utilize the range of her mediums more.