Since no one else has said it on this thread: Welcome to AC! Nice to see another flatland SW person!
Sounds like you are getting pretty good advice from everyone. Here's my 2cents:
If you really want to get a lion, get the best skimmer you can afford. Lions are very messy from both ends! A skimmer will pull a lot of that out of the water, so you don't have to worry quite as much about water quality.
You can do a search on skimmers to see what the concensus is on which brand vs. price is the best.
Fish only tanks are cheaper than reefs, if only because you don't have to pay for all those corals, etc.-but they sure are beautiful to look at!! I have horrid lights on my tank, so I have so far managed to tell myself "no!" on corals, but i sure do like looking at them & wishing...
You also don't have to fret as much about your water quality with a FOWLR tank; most fish can put up with poorer water quality, while most corals can't.
As far as lights are concerned, like someone else said-buy the best you can afford. There is a website - ahsupply.com - which sells light refit kits, if you are something of a handyman. I've heard lots of people say the kits are easy to use and come with good instructions. So, if you have the lights that came with your tank, you can use the kits and put them in the original light hoods. There are limitations on this, though-you don't want to get carried away & have a mass of melted plastic on top of your tank!
I agree with CHughes on the rock-you will want at least 75 lbs, and the higher you go towards 150, the better-all the critters in the rock eat all the stuff in the water, so you have cleaner water. A deep sand bed will help with this also. You don't have to get the expensive sand at the LFS. You can go to Home Depot & pick up the playsand they sell for sandboxes cheap. The most suggested kind is Southdown, or Old Castle, since these are aragonite sand, and will help keep your ph up, among other things.
Powerheads-lots of variance here-the only one I've heard not to use (a lot) is the Rio ph's-they will work fine for a while, then will blow up & spit oil all over the tank & kill everything.
HTH!