I understand your position
I'd never leave th7 without maxed walls.
You will likely use many of the troops you don't use now later in the game. Upgrade them all.
Upgrade your stuff so your time at th8 doesn't seem so long.
I can tell you that it is a huge jump to th9 and you don't want to miss a thing while it's easy. You've played a long time and want to reward yourself but every jump is bigger and badder and harder in this game. Don't be too hasty.
If you're not killing it at th7 then you either have to lower your farming level or upgrade your troops or look into another attack group. I'd have never left th7 if I had any single thing to upgrade. At the very least, I was the best contributor in my clan.
You should be murdering 'em at th7. If not, seriously check out your attack plan. If you're impatient about a jump in th now, think about how long it will be at th8 when you have to do all those walls right?