Sounds like you have a good start on your new tank.
The first thing I would note is that 2 AP9X will cover a 125 but the bracing can mess up the light distribution. If you have a tank with a single brace then the 2 AP9Xs is a great option. If you have 2 braces then 3 lights would be a lot better.
For circulation pumps, I would look at getting 2 controllable pumps for either side of the tank. I would recommend each pump be rated for about 20-30 X turn over so you are looking at the 2500=4000 GPH range. The nice thing is you can always turn down the pumps if they are too large. I am a fan of traditional in-tank propeller powerheads so I would likely go with some
Octo Pulse or
Tunze Streams.
For your return pump. The first question I would have is what size drains do you have? We would also need to know how you plan on plumbing the drains. Full siphon drains can handle a lot more flow than gravity drains. Assuming you are using 2 x 1in gravity drains then I would look at a pump rated at 800-1000 gph. Any more than this and the drains can get really loud. If you are using a full siphon drain then you can go bigger. I think the new
Lifegard DC pumps could be a good choice. I have been impressed with how quiet they are for the price and they can always be dialed down if the noise is too much.
Others will have their own equipment preferences but these can get the job done.