most hubsets are sold same number front and rear. at least that's what I've commonly seen.

I have 28 3x front and back. I would've gone with more spokes but I got a set of 28H Aeroheads for $5 at the swap meet so I opted to just build them. They've lasted 2 years apart from my front axle threads stripping (don't buy suzue basics) riding normal to rough roads all over california. I'm only 135 lbs tho.