i can give you an small guiding about that.

the max stats you can put on a equip are 3,5 of one type or a lil bit higher of more than 1 stat (together only). this does not work for every armor piece but for the chestplates , ats and a few it does.
to get max possible stats on a armor you need 1.00p components and master recipes. master recipes do unlock after lvl 80 in each craft and 1.00p items can be found in diffrent ways. for critter parts you need to kill mutants at max age ( mitants give 1.00 to a stat, normal animals only 0,75 )
for items like cloth, metals and other scrap you need purple stuff, the chance to find this is slightly increased with the higher danger of the zone you are searching in.
(most, not all) resources have 1.00power already. that helps for simple crafts like basketry.

you need at least 90+ quality to be able to use components in a "master" armor recipe.

please use DDT's Crafting Table to make sure you get the perfect stats out of your materials.

about your suggestion, there are sooo many items and so much information you want to see in a tooltip, that i dont think it will be implemented. that will be weeks of work and calculation plus the calculation will be based on your charackter which means the server have to calc it for everyone again. your skillvl and stats are what effects a lot to the quality you do. also the game wont know which kind of tools you use, the one which add a bonus to your craft, normal/artisan/master, the upkeep bonus you set in your tribe.
its something which is very hard to calc and DDT did a very well post about it which is a lot of effort already. just try stuff and figure out how it works for you. i'm trading all kind of armors and weapons in 110-117quality with high stats ( not on weapons ) but they will be expansive couz the items they require are even for vet players hard to get. you can ask me anytime and i can calc what i'd want for it. Pean~

Thank you Peanuts for pointing at that DDT table.. very handy stuff. And I must agree that it would be a lot of calculations and we probably don't want to add more pressure on server :). But to be honest as long as we have something like this DDT table we ok. Thanks again.

I would like to see a preview of the stats/quality would be a great thing, and I'm not sure how much stress it would cause but I think if that is an issue, they could limit the preview to like one per 2 seconds or something.

This could certainly be done, but it's not a quick and easy thing to implement. It's a good suggestion though. Thanks!