I used to love those cross country tyres! Really quick, but surely they’re going to be really old and perished by now?
Anyway OP, as someone who also rides the odd CX race (Northwest league) on an MTB, if you accept the fact you’ll be in no way podium bothering don’t worry about the width of the tyre too much, just get something on the faster rolling end of the all-round spectrum. Any places you make up will be down to superior cornering ability and a gung-ho attitude on technical parts of the course* so you want a tyre that plays to those strengths rather than trying to replicate a flat-bar cyclocross bike.
*I just love smashing down slippery hills, getting air over jumps, sliding round hairpins with my foot out etc. when all the CXers are going steady.