1. Will this light be ok when i want to grow a few corals later down the road? It was doing fine when they had it setup on the counter....just want another opinion.
-well, it really depends on how crazy you want to get...personally, i would want more light especially on a deep tank like the via aquas, but for mushrooms, leathers, and zoanthids you could probably get by with what is on there...for sure on the shrooms
2. I still need to get a heater, what wattage would you recommend?
-50w assuming your house doesnt get really cold
3. I'm thinking of getting a small like AC Mini just to move some water (along with a powerhead) and maybe serve as a fuge later on.
-if you have the space/money i would just get a larger AC...maybe AC 500; a lot of people go that route and here is a link with some more info
http://www.californiareefs.com/tank7reef.htm
-wouldn't need a powerhead with the larger AC, and you could add the heater to the refugium!
4. LR. Any poundage recommendations for a 15gal? This isn't a very wide tank, its taller than anything so i'd stack the rock.
- its really hard to give a poundage estimate on such a small volume because if you get one light piece or one heavy piece it can really skew things, but i would guess around 15-20 pounds would be good. you need to make sure the fish will have a little swimming room (though clowns and gobys both don't move around all that much). my advice would be to be selective. don't just buy a piece to get started, really look carefully for something which has a lot of interesting nooks and crannies and holes. you might even consider looking for one nice large piece and not adding anything else (i think that is what i would do), especially if you go with the AC refugium because you will add LR to the ac as well. realistically, in an unskimmed small tank you are going to need to do significant w/c anyway so the difference between 15 and 20 pounds of LR in your display will be negligible
as far as stocking, i think a pair of percs (i prefer the blacks myself

) is about the limit in a tank that size and would skip the goby, but shrimp, crabs, and snails, are no problem and add very little to the bioload...probably a good choice shrimp wise is a single specimen of the lysmata species...might go for a blood shrimp in your case because in such a small tank you would probably even get to see him or her, lol
anyway, hope that was somewhat useful to you