Fast craft variant/homebrew

Hey All, so crafting came up in some conversation in my group and I think in order for crafting to be useful in my game (dnd 3.5) I need a variant rule. Here were my thoughts.
Instead of crafting taking multiple days or weeks players are instead able to craft items during resting time (meaning any time the party sleeps to regain spells etc.) My party does a lot of dungeon crawls and not a ton of city exploration meaning they rest maybe once per session.
I am not sure yet exactly how the variant would work and am open to suggestions. My thoughts are as follows not sure how much of this to use or if it is balanced so looking for feed back.
1: You can make one item craft check per rest at no penalty.
2. You can make additional craft item checks but each of them are at a penalty, -2 penalty for the first check -4 for the next etc.
3. Items that do not require checks such as items that can be made with item creation feats you can make as many as you want as long as you have the gold for it
4. Items would require traveling stations like an alchemy kit, a spellcasting rune circle, or a portable forge.
Thoughts? Better suggestions?

Arrows, bolts, and bullets should still be in bundles rather than as separate checks unless masterwork or to be enchanted. Maybe shuriken too.

More Traveling Stations: wood-crafting kits, cooking kits, summoning circles, protective circles, stonework kit, herbalism kit (probably required with alchemy kit), poison ID kit, poison creation kit (requires either alchemy kit or herbalism kit), healing kit (requires herbalism kit), tanning kit (requires skinning kit), skinning kit, armor-working kit (requires portable forge), armor-repair kit (requires portable forge), sewing kit, easel and paints, paper and ink (requires alchemy kit for magic scrolls), potion-making kit (requires alchemy kit and herbalism kit), blade repair kit (requires portable forge), brewing kit (requires either herbalism kit or alchemy kit), leatherworking kit (requires tanning kit and skinning kit) and portable altar.