Ed,
First, welcome aboard! We're obviously biased here, but Festool is a great choice. Now about the "first products" choices...
This is a tough one. IMO, you need all three. They are tied closely together. Unless your primary purpose of using the TS55 is for breaking down sheet goods, the MFT1080 and TS55 go hand in hand. I'm constantly using my combo for cross cuts.
At the same time, the CT22 and TS55 go hand in hand. I ALWAYS have my TS55 hooked to my CT22. Well, not always. A couple times when focusing closely on the cut line, I didn't notice the CT hose slip out and wondered, "why is so much sawdust flying around?" ;D
About using another vac... I don't know about the Ridge, but Fein makes an excellent vac. If you have one, you'll be set. OTOH, if your choice is between buying a Fein and a CT22, then I'd strongly recommend getting the Festool CT! While the Fein in a good vac, it's NOT part of the Festool system. You would be integrating two systems and options like adding a Boom Arm or Hose Garage, and using the CT for systainer storage are not available to you.
Corwin made an excellent point about Festool systemness and I'd like to add to that. Essentially he said, "the system is greater than the sum of the parts" and the system is multifacetd. What is REALLY key here is that, when you buy the pieces that meet your needs, it doesn't become A SYSTEM, it becomes YOUR SYSTEM.
Your needs are different from Corwin's, Skip's, Howard's, and mine. Therefore, YOUR SYSTEM will be different from MY SYSTEM. And YOUR SYSTEM will change as your needs change. Some days (or hours or minutes), "my system" is a "build your new shower walls system" - measuring and cutting studs for my new shower. Some days, "my system" is a "sheet rock cutting and routing system". One day it was a "build a small workstool cutting, clamping, and glue-up system". One day, it was a "production line cut, pre-drill, and screw together 32 support jigs system". Today, in about 30 minutes, it will become a "assemble and install electrical fixture system".
My Festool "systems" change dynamically to meet my needs at that moment WHERE the needs are located. I take my systems on-site, but "on-site" for me means moving my system to the garage for sistering the joists, or into my master bath for a remodel, or into the back yard for refinishing the back deck or rebuilding the fence, or into the house crawl space (it's a big one) to build a new storage deck/shelf, or to any room in the house when I install new moldings.
That's why I love MY Festool system. I hope and expect that you will love YOUR Festool system.
Regards,
Dan.
p.s. if at all possible, get the TS55, MFT, and CT22 combo together. That's what I did and haven't regretted it.