If you could do it all over...

[intarsiabox]

I've always had my sump stuffed in the stand under the tank. For my last tank I went with an external overflow and had the sump behind the tank with lots of room all around it. I couldn't be happier with that set up as I had unlimited access and wasn't restricted on the size of the sump so no comprimises had to be made for skimmers, pumps, etc.