No one has mentioned that nickel silver frets smell disgusting.
Iāll be the nay sayer here 
The only issue I have with them is that hammer ons sound different when playing clean or edge of break up patches. Sound ping, but not sure if it was just that guitar, a custom grosh electrajet VT. It was a bright and light guitar, ridiculously bright, on the the other hand I played an Xotic tele with a rosewood board and huge frets, didnāt hear this ping thing on that one but I think we were playing with high gain, canāt really remember. So to be honest my sample is too small to be sure, but I still stick by nickel for now, dunlop 6000 on all my guitars. Would love to try the jescar evo gold, heard they are the best of both words.
Disclaimer, these are my personal findings, everybody comes to their own conclusions about these things Iām sure.
- taller frets, less fretboard contact, easier to fret as there is less fretboard to push into.
- same logic for scalped guitars, zero push back on fretting
- great for bending as thereās less or none rub against the fretboard.
- as itās easier to fret, playing with higher action is easier
- notes ring out better with higher action
Been reading the comments of singing and playing, I have a decent blues voice but so damn shy and feel so damn stupid doing it, Iām almost 50 and in a severe SRV phase. Itās going well, I just wish I can start to get the voice going without feeling weird.
I think I need some therapy on this one thing.
edit: oops, I think I cross posted on @Drew 's NGD post about the singing. Sorry.
Iām not saying this ISNāT the case, as it very well could be. But, as a guy who even though his picking is worlds better than it used to be, still has 30 years or so of legato vocabulary annd phrasing at his disposal and legato is still his default choice, Iāve never noticed a difference in legato attack on my stainless vs nickel steel guitars. There are any number of possible explanations for this and the fact Iām a ābright guitar into dark ampā player may mask any slight differences fretwire imparts, but at a bare minimum, if someoneās reading this thread and suddenly worrying about the tonal impact of stainless, Iām at least a single data point in the ānegligibleā column.
Personally, I always assumed that the āstainless makes your guitar sound brighterā thing was an urban legend pushed by luthiers who hated how much faster they went through tools on stainless, but honestly if it IS true, that might even be a plus for me! 
Yeah, I think itās more of an issue with clean to break up tones, with legato drive ,itās a non issue, and probably an advantage as you say.
I love that SS lasts for ever and is super smooth on the bends, but try to hold a note with vibrato for that rare 10 second shenanigans and some weird friction develops. Edge case.
I donāt use THAT much gain, though, and I havenāt noticed it it clean either. Could be the rest of my signal chain, or it could be the ears and preferences at the other end of it though, who knows!
Iāve heard people suggest thatās an upside for nickel steel, actually, that the slightly higher drag means if you hold a note with vibrato you actually get a little more sustain from a āviolin bowā like effect from the fret. Again, I have no clue if thereās any truth to that. 
I played an Yngwie Malmsteen strat a few times and I gotta say I really enjoyed the scalloped frets.