With the V-6, there is usually some amount of depression of the brake pedal before you feel pressure, and since the pedal feel is the same as before, what you are experiencing is likely normal. As long as you started with the tire that was furthest from the master cylinder by the way the lines are run, and worked your way back to the closest, you should be fine brake wise, I would be more concerned with the brake lines that may have issues with rust like the one you found.

More than tread lightly. Leave it like you were never there, nor anyone else.
'90 X-cab 4.88's 33 BFG AT's, rr ARB, Headers, Ignition upgrade, cold air induction.
'91 X-cab 5.29's 315's BFG MT's, rr ARB, custom bumper and flatbed