Is there a section on the site that discusses Sound bars?

I thought about it a while back for my Mum but decided I couldn't compete with a £200 ready made soundbar complete with sub.
With full size speakers, the economics of large boxes make DIY more cost effective.
Nothing to stop you doing it for the fun of it.
 
If you use high powered amps and (bigger) speakers, it stops being a sound bar and becomes a powered speaker.
If you want to go big, build a system with full size speakers.
To get the features you want the simplest DIY route is to hack an existing sound bar for the clever bits & add whatever amps & speaker you want. This has been done.