I think they lack a bit of base and the ones I currently have are really designed to go on walls and not to be used for home cinema.
On the contrary, bass-lite designs are
exactly suited for home cinema. Certainly more so than for use in music only systems!!
Home cinema rigs provide extra bass from the sub. So if the main speakers are bass-lite then it doesn't matter so much. This is the principle of all those sub-sat systems with small satellite speakers.
The conclusion must be that your home cinema amp is set up wrong for the speakers you have, or you are using the amp on the wrong setting for music given those particular speakers.
Your speaker set-up should be
small for L&R, Centre, Surrounds.
Crossover point should be at least
80Hz, but
100Hz is probably a better choice with those Q-Acoustics rears.
You'll need to adjust the sub controls so it blends well with the fronts & centre. Put some music on, put the amp in a music mode other than direct - you want the sub working with the fronts. Try the phase control at 0 and 180 to see which gives deeper bass. Then adjust the bass level to avoid boom.
As for a speaker upgrade, I'd echo what others here have said: Good quality s/h standmounted speakers are a better use of your budget. New but cheap floor standers are a false economy. Your heart wants them, but unless you have really low standards the reality is there's not enough money to make the big rigid heavily-braced boxes required to make £150 floor standers sound okay.