Changing Tank advice

[1stmardiv]

OK, We currently have a 150 reef tank. It is 72" x 18" x 27" deep. It is drilled in the bottom with bulkhead connectors. We are resetting our tank and thinking about getting rid of this tank and doing a same size footprint but shorter tank to (1) make maintenance easier and (2) allow for better light penetration with our 3 250W 10,000K halides. We are also boilding a new sump with a 75 gallon tank. Question is, do we go acrylic or glass and what kind of arrangement should we be looking for as far as overflow boxes built in. We want to make the right choices, so pros and cons would be great for this topic. Also we will be looking to sell our 150 tank when the tranfer takes place. We plan on locating our 75 gal sump in the adjacent room dirictly below the rear wall of the DT. Any ideas and comments would be appriciated. We like the idea of the shallower tank for maintenance reasons. The 27" deep was always tough to get into.