OK, I understand what you mean. You don't need to use the chain tensioners if you're running a rear mech, because the cage and pulleys on the rear mech are sprung to keep the chain tight, even when the length of the chain changes as you shift gears. If you're still going to use the rear mech, you don't need the tensioners. The quick-release should be strong enough to hold the rear mech on, provided it's a good-quality one, I've seen a bike with a rear mech like that and quick-release wheels once before.

[Edit] If you're thinking about the cone wrench, you'll probably need two sizes, front and rear hubs use different sized bearing cones. Most likely sizes are 14mm for the front and 15mm for the rear (at least that's what my MTBs all seem to use) plus a wrench to loosen or tighten the locknuts. It's fairly simple to adjust the bearing cones, which you'll have to do if you swap spindles around, but it might take you some time the first time you try it.