Cool, another Picotope owner! Mine's FW planted though, never made the leap in SW.
Details in my signature, for the light a Finnex 12" fixture will fit your tank, and the Ray2 can be had in actinic/white combo.
Had a similar lid problem, ended up cutting my own out of thin cheap acrylic from home depot. Yes it will bow and/or scratch - but it is cheap, easy to replace, and I just flip it over every day when I feed (take it off when I am there it enjoy it.)
Good call on the Aquaclear filter, using a 30 on mine.
You can mirror the back very easily, the tank is small enough to use a precut piece of mirror. (mine was from a dollar store mirror in a frame)
That Picotope logo in the front peels off if you like, I got tired of it being in the way.
Current pic (time for a big trim!)