If you get cold easily and plan on diving the great lakes regularly any wet suit or even semi-dry is a waste of money. A drysuit will allow you to do multiple dives and be warm. I've seen a number of wetsuit divers in Erie and while those in drysuits are fine, wetsuit divers either do one dive and sit out the next or in some cases, don't even make it to depth before bailing out.
A drysuit is also highly versatile. Vary the undergarments and you can dive dry in Michigan one day and be comfortable in Florida two days later. Just put less on underneath.
Also for very cold water, if you have to have a scuba pro reg, the Mk17 seems to be favored over the 25.
You can also choose from numerous other brands that will be less expensive and perform just as well.
Many new divers make the mistake of spending money they don't need to by purchasing the gear they think is what they want. I did. Then a few months down the road I realized it wasn't suited for the type of diving I wanted to really do.
I try to find out what a person's interests are and advise them to buy their second set of gear first.
If you plan on the great lakes, that's cold water and with a drysuit, a back plate (steel) and wing will allow you use less lead, be adjusted to fit you, set up the way you want it, and be completely modular so that if something happens to a part of it you only replace that part. Not the entire BC.
When choosing things like a mask and fins fit is key on the mask. Brand, color, style, etc are pretty much irrelevant. As is cost. It has to fit or it's garbage. I don't listen to anyone when they say that "oh, you should get the XXX model from YYY, it's a great mask!" Take that with a grain of salt. Unless you have the exact same face, that advice is just as irrelevant as what color it is.
Fins. I had a set of rockets. They fit a VERY NARROW range of feet and the foot pockets were junk. Try different fins and find the ones that fit. Much better fins out there. Try several pairs before you buy and stay away from gimmicks like hinges, power bands, etc. Also, claims of how fast you will move with said fins? Worthless unless you plan on competing in speed trials with them. It's not a race.
Snorkel - get the cheapest simple j tube you can. I sell one for 15 bucks. Dry snorkels are gimmicks and ok for snorkeling for those not properly trained in snorkeling, but divers need a snorkel you can take off the mask and shove in a pocket or roll up. Most leave it in the bag on the boat.
DON"T BUY A CYLINDER YET! Especially an al80 for cold water diving with a drysuit! Try aluminums and steels. A steel would be better and will be a better value. Buy used steel cylinders. You'll save money up front and in the long run. Due to a bad batch of aluminum in the late 80's early90's many shops won't fill al cylinders more than 15 years old. No good reason for that but it's what they do. Some hydro facilities don't mess with aluminums older than that. Steels last much longer. I have steel tanks from 1954 and 1957 that still pass hydro every 5 years. Steel tanks have better buoyancy characteristics. As a result you'll use less weight depending on the ones you get.
I have an entire chapter on equipment in my first book about choosing it that also looks at how the pricing on gear works. Don't get talked into useless crap like I did that's gathering dust or was sold or tossed a year later.
The ProPlus is not a bad computer. I prefer wrist mounts over consoles myself.