Have you looked into Eurorack Modular Synthesis?
Yep way to complicated for me.Maybe at a later time when i feel more comfortable with synthesis i will give it a try.
After this detailed interview with a Yamaha Designer I must to buy the Yamaha DX today
https://www.dropbox.com/s/fqazofq0gxezztq/IMG_0029.JPG?dl=0
Thank you for the many tips, seriously 
If find this interesting, the recent synth when it comes to FM, now with affordable prices:https://www.gearnews.com/modx-yamahas-awm2-synthesis-and-fm-x-technology-synthesizer-gets-leaked/
Seems to be marketing crapware. Not the state-of-the-art FM synth, but a crippled, multilayer performance keyboard for pads and plucks only or something, very raw average joe sound. Sorry for this link.
EDIT: Now it turns out that the MODX has exactly the same engine as the Montage, and now there are much better videos with demo sounds available. It sounds very good. Crappy marketing campaign, though. In deep videos still are missing. But the reference manual now is available:
https://usa.yamaha.com/files/download/other_assets/2/1192582/modx_en_rm_a0.pdf
So it is 64 voices of FM-X, which is capable of all of DX7 + a lot more, 128 voices AWM2 sample/synth engine, 2 insert fx per timbre, triple master fx section and a vocoder.
I have a feeling that this winter we will have more synths.I am going to wait and see
I have a controller and would never buy a hardware synth.
Preenfm2 Low price good FM Power