primes to replace holy trinity

Hi all..

I have 24/70  70/200 and 17-35

what primes would make a good replacement for these lenses ..I quite often shoot at 70 mm and 35 ish..and not much else unless using the 70-200..and mostly that's at 200 mm...a 200F2 is out of the question due to cost...

I was thinking perhaps a 85mm F1.4..but that's as far as i've got

reason for a possible prime switch is less weight.....so perhaps keep the 70-200 and replace the other two zooms with say 2-3 primes ?

suggestions would be helpful and if anyone else has done the same swap was it a good move or bad ?