Homebrew PCBs

I've tweaked my UV box to even out the intensity (somewhat, not 100%
perfect but good enough).  I'm ready to actually use it now :-)  I've
got some questions about steps in the photo process that would be nice
to skip or otherwise cheat on:

* Developer/stripper chemistry - is more concentrated ok?  Not optimal
  from a cost point of view, but I'm thinking of time-between-discards
  and shelf life.

* Developer/stripper temperature - I can use warm water to mix it, but
  heating it up for use might be tricky.  Will it work at room
  temperature, albiet slower?

* Laminating - hotter OK?  My laminator doesn't have a heat setting,
  and the hot air gun is too unpredictable, so do I err on the side of
  "hotter" or is "just right" important?

* baking - 212F for 5 min after developing.  How important is this?
  How critical?  Hot air gun OK?

* bubbling/agitating developer/stripper - how much of an effect is
  this?  With the containers I have I could "swish" the boards around,
  but that's about it.