Relief = minimal .003" or a bit more treble side and .005 or more on the bass side, of course we have to accept less than optimal on the treble side or the bass side to conform at times. So I observe the treble side and if it has more relief than the bass side, not what we want... I take the bass side pretty straight such as .003" relief and the treble side will have more than optimal relief but that's better than no relief or backbow.
Height at 1st fret = Forget it we don't use the first fret except for how we cut nut slots which is a different conversation. We measure action at the 12th and that's a pretty standard industry thing. The nut slots should be cut properly before you adjust action. It's a bit of an art to do very well and take them low but not too low. Not something that is easy to explain here although I've tried many times.
My approach to setting up an instrument is:
1). Adjust truss rod
2). cut nut slots (all other specs will be changed if you do not do the nut slots first)
3). observe action at the 12th
4). set to specs at the 12th
5). play every note to make sure they don't rattle or buzz (not every note but sample plenty of regions where people do play)
6). Set intonation
7). play a tune that this instrument is famous for. For example I would play Hendrix on a Strat and John Price on a Martin
8). stretch strings so the show can go on with less fiddling
Point being there is a sequence to my approach and it works great for me.
Height at 12 4th string = The g I set for 5/64th. The e I set for 7/64th. A heavy hitter, five or six string, slack tuning all change these numbers and it's important to know if the player is using drop tuning, beating the thing when they play, etc. All strings between the g and e on a bass get progressively higher as you approach the bass side. Example the A would be 6/64th and the e 7/64th.
Height at 12 1st string = Again I do 5/64th" for a generic acoustic or electric bass, strings, player, etc.
That happens from time to time.