Thanks for the reference to John Darko. I respect he's making a living from things as pleasant as listening to music and dealing with hifi gear. Apart from that the LS50 needing expensive amps to compete with the Wireless is just as much widely accepted as them being impossible to integrate with subs (unless you let them run full range). In other words: I wholeheartedly disagree. From my personal experience all they need are quality amps (of course) that can deal easily with 4 ohms load (as the LS50 is not really an 8 ohms speaker, despite KEF's claim).
So far it looks like your sonic problem is theoretically solved, leaving you behind with the budget problem of not being able to sell your previous gear. So, where to go from here?
Shelving out more money on new speakers might or might not help. I have no doubt the Metas are even better than the already excellent LS50 (my dealer describes the Meta as a "small improvement", but I didn't have the chance to listen to them for myself). But this move will certainly not lower the burden on your wallet. The outgoing LS50 has been available so dead cheap, 2nd hand prices are probably completely spoiled, still.
Maybe the TDAI-3400 would have been a more suitable replacement for your separates, but the invest would have been noticeably higher, definitely not cost neutral. A 2nd hand TDAI-2170 (which is out of production now according to many sources) with its plethora of input modules and outputs could have been another option, keeping the streamer at least. But selling the 1120 now will surely result in further monetary loss (plus Lyngdorf claims it to sound exactly the same as the 1120 from the amplifier perspective).
Go figure.
@karlsushi, everyone as he likes.