I wouldn't order any holes in the top. That will just be spots that humidity will escape from. Just mount a RHP for the heat since they are more energy efficient, don't dry the air out and don't ever need to be changed. Check out http://www.reptilebasics.com/rbi-radiant-heat-panels or http://pro-products.com/ . I personally use Pro Products ones but they are more expensive but very nice. With an RHP you wont need a UTH but you will a T-stat like a Herpstat to control it with. If you want lighting in there, just get LED lights or an 18" or 22" fluorescent fixture from Home Depot. I use http://www.homedepot.com/p/GE-18-in-...6466/100384834 in my cage and it works fine.
I too am looking at getting my little girl an AP cage or another Pro-Line. If I go AP, I will be getting a T10 with sliding glass doors and that's it. I will order and put in my own RHP and lighting as its really easy. I will do the T10 as I want that extra height for the RHP as I don't like anything sitting too close to it.