If you're thinking of a 75g, trust me, go with a 120g instead. Depending on where you are going to put it you can with internal drain, or as a peninsula with the external overflow on one end instead of the back. As
@PicassoClown said, a peninsula tank would give you more options for scaping if you are able to view it from all sides. I wish I would have done that instead of the 75. a 120 just offers so much more real estate, and if you go rimless.
As for lighting, the best single LED fixture option for either a 40b or a 75/120 would be hands down a
Reef Breeders Photon V2+. They come in multiple sizes including 36" and 48" and are fantastic lights. I was shocked when I learned that they use the same LED diodes as AI used for the Hydra 26 HD's. Light coverage area is amazing with them because how of the LED's are spaced out. Probably the closest one can get to T5 coverage in a single LED fixture. You can mount them with the included tank stand mounting arms or suspend it. They have a 2 year warranty and Logan is awesome when it comes to support for it. I ran one for nearly 2 years and they grow coral like crazy, produce wonderful color pop and are easily configured for any color spectrum you desire. The only down side is getting the channels set correctly can be a bit of a challenge at first, but you can use similar settings as the Hydra's to get the right spectrum then adjust the power per channel numbers where you want them with a PAR meter.
For a skimmer I'd recommend a
Simplicity Skimmer either the DC120 or 240DC depending on the tank size. I have the 120DC and that thing is an absolute beast for its size. Mine never ceases to impress at how much it will pull out. They run about 1/2 the price compared to comparable brands and are very reliable, relatively quiet if you have them in a cabinet or modify the intake silencer. Being a DC pump, you have a high level of control over the pump speed as well as air intake. My only complaint with it is it can send off a fair bit of micro bubbles from time to time because of how the outlet is setup. I have toyed with the idea of modifying it so the outlet is closer to the surface instead at the base.