the problem with adding bluetooth is that it instantly makes a unit obsolete... eventually
are you happy with just AAC/SBC? because that's what you get in the SMSL C100
even if they add aptx-hd there will be a day when this is obsolete... and people ask for LDAC and aptx-ll etc.
there exists a market for cheap BT dongles that wire into the digital inputs that you can discard ones the technology catches up
to me BT is a convenience item, and i dont think you need better than AAC (but that's just my jaded experience)
people ask for this and that and everything and really, that shit already exists in a $100+ dac
btw. i just googled "BT audio receiver" on ebay etc and you get the gammut of cheapo $5+ chinese gear... some have digital out, some have remotes, some had screens, some have USB memory support... there's a LOT out there... you just have to find one that has the stuff you want in it
its too much for me because I dont really use this shit but I do get a 'buzz' seeing how in China, they really dont want to leave a void in the market and if people want bluetooth audio receievers they will damn well make a million of them for chump change.