I've also been pondering about this and I've found plenty of things that can replace existing enchants, I'm not sure if that's what you're looking for, but I figured it won't hurt to post what I found here (I think most of this is pretty common knowledge though among experienced FTBers).
A Macerator can double as a fortune enchant for most ores. I think Coal ore is the only exception to that rule (giving you only 1 Coal per ore, instead of 1-4 like normal). Diamond ore isn't the best either (giving 2 per ore), but with fortune you also get roughly 2 diamond per ore on average. All other ores have very good rates in the macerator.
Silk Touch can be obtained with a Rockcutter (a rechargeable tool from the GregTech mod).
A Chainsaw will suit all your wood chopping needs, acting as shears on leaves (and sheep/other things you can use shears on) and cutting through wood quite fast.
The Portal boots are the perfect replacement for feather falling boots, they can't break and negate all fall damage. I would agree they're a bit unbalanced, but most stuff from the portal mod is I think. If you don't want to use them I think rubber boots from IC2 are a good alternative (they negate fall damage for the first 10 blocks or something, which will reduce the damage from high jumps a lot).
For other armor you can resort to rechargeable quantum/nano suits which will protect you from lots of stuff.
So I guess that only leaves swords and maybe shovels. I do know there is the Nano Saber, but I don't know if it can mimic any of the sword enchantments. As for shovels, a mining drill will cut through most stuff you use shovels for without any trouble.
Personally I just use the Chainsaw as a sword replacement though, it can kill creepers and skeletons in 2 hits, zombies usually in 3. I don't care all that much for mob drops, if I really need them I'll go cave or hunt at night until I set up a mob trap that is. Though I wonder if mob traps are still worth building with all these mods xD
Anyway I hope you can use some of this info, in the hope I didn't write all this for nothing

xD