I don't believe that
Sign/verify speed must be not lower than 100 signatures per second on a 1 GHz CPU (1 core)
can be achieved.
I have working implementation of nrs:
https://github.com/moadib/nxt_crypto_jsOn my PC(core i5 2.6ghz) algo took approx 200ms for one signature on Google V8(chrome, nodejs).
I'm also tried compile c++ code to js with emscripten and it give approx 2x faster unreadable file. This is not enough too.
P.S. also i think that other(which not have Google V8) browsers will show worse results
I've seen found Curve::sign to be relatively fast, but i agree that it seems unlikely we'll be able to get Curve::verify to be fast.