Its a tough decision - with your current set-up, you may not optimized the use of your gears since you're going to be in a smaller place & close neighbors pa. If you could live with turning down the volume so you dont rattle the neighbors, then thats fine - but yung nga, you wont optimize the use of your gear.
Kung mag HTIB ka naman, you will loose a bit of sound quality and dynamics compared to your existing set-up. Again, if you can live with that then go HTIB route.
You may also consider going somewhere in between - change your FS to BS, as they're more musical even at lower volumes. Surely, you'll loose some bass when you switch, but you can also explore a powered 8" sealed sub sometime in the future.
Pakiramdaman mo muna yung new environment mo and if you think its safe to change/add equipment slowly, then you'll have a better judgement of what to do.
