I don't believe a trickle system increases your bio-load at all. It does a good job of supporting bacteria to convert ammonia an nitrites, but your nitrate levels will just sky rocket. unless you do larger water changes of coarse. Putting Live Rock instead of the bio balls provides he same, if not more, surface area for bacteria and the rock, depending on the individual piece sizes and types, does not trap as much detritus as bio-balls would.
As for the temperature, it wont see any kind of temperature change. If you are going for a reef, and cannot afford/do a chiller....i wouldn't do a reef at this point ;p. Don't rush into something that you will not be able to control 3/6/9 months down the line. You'll simply run into problems that you could have easily avoided. | 
