Thanks for the responses. I've updated the webpage with my latest plan and an elevation.
You all have good suggestions. Most of what I'm doing is for pretty good reasons, mainly that I'm just getting into this hobby and I really want to have a space that is out of sight out of mind.
As you'll see by the floorplan of the house, this space really is unused and out of the way which is a huge priority for me right now. I'm luckily a pretty small guy, so the small space will work ok. I agree that it's not luxurious, but i have two small kids that require most of my time. When they grow older I may take over the guest room as a very nice large space.
Ventilation-I had originally planned on routing exhuast out the existing crawl space access which is high on the wall anyway. I've done some tests though, and since the furnace is in the room there is plenty of ventilation. If I have a problem I can always add a fan. As my mechanical engineer friends say, "the solution is in the dilution". If and when I get into the stinkier chemicals that some of you mention. I may have to re-think this. I do like someones suggestion for the tray covers.
Stacking trays-I've acually thought about this, and this will be my solution when I grow beyond the simple developer, stop, fix, wash system that I learned at the community center.
I've decided to locate the sink on this wall mainly because the other wall is solid concrete and I would then have to furr it out and /or come up with another routing for the system. I'm trying to make this pretty painless.
To be honest this will be a learning experience. I got into printing a few years ago BK (before kids). I've only printed three times since (last 4 years), but haven't lost that itch. Since then I've gotten a medium format Ricohmatic and a 4 x 5 Graflex Supergraphic to tinker with. I've never even printed anything larger than a 8 x 10!. ROOKIE!!
Anyway, I appreicate all of you helpful suggestions. I'll be lurking around these boards trying to pickup anything and everything I can. Thanks again.