Nice question.
I like to think this program as a Simulator. I don’t fly IRL since 20 years. I quit flying FSX 10 yrs ago, when I was flying the Citation. So, as I would have done in RL, I statrted over with the 152 in local flights from a closeby airstrip (I live in Toscana, Italy), then switched to 172 for Italy-wide flights, then Bonanza for a round Mediterranean sea tour, actually on the TBM, with which I crossed the Atlantic (via UK, Iceland, Greenland) exploring USA. Actually flying the Oregon trail from Kansas city to Portland (always been one of my dreams). So fun. As addons, I got REX Weather, then Rex Global Airport, and the TBM improvement. Now planning a 4 season/vegetation mod, but not sure which one to choose yet.
I was long waiting for a sim like MSFS. The scenario is more than I could expect to see sitting in front of a PC. All the bugs will slowly be fixed, either from the developers and the users workarounds. And it will constantly improving…
C152
C172 Classic
Savage Cub
Mooney 20R
Thanks for the great topic! Just something positive for a change 
For me the Cessna 172, because I flew that plane three times irl. Then the Cessna 152, because I dived into the flight trainings of Jayne and Forder on this forum. Third and fourth were the Daher and C182, because the C172 wasn’t able to clear the alps and kept slamming into the mountains because of icing. After that any plane that was used in a certain bush trip or VFR training session from FS Academy.
At the moment I am building the GNS530 and 430 into my cockpit to replace all the logi radios and panels. That will add a whole new dimension and something new to learn.
After that I want to dive into Vatsim and IFR procedures.
172
TBM 930
Citation
Been studying the FBW A320. Did the FS Academy Airliner training and watched several FBW videos. Aquired the checklist and will now start studying the MCDU configuration process.
Hope to leave the ground on a maiden voyage before the end of the year. Still have a lot of ground work to do.
My first flight was a Cessna 182 back in the 1980’s on my trusty Commodore, in what was Sublogic’s Flight Simulator II… God I’m old
Now I fly exclusively the FBW320 and have several hundred hours tucked under my belt!
First was C172 steam gauges, but I soon moved to the G1000 version because I love to play with modern technology.
Later I moved to the TBM followed by the WT-modded CJ4.
I think my next one will be the Baron, because I want to learn how use prop levers. That and the fact that it gives me a chance to try my Bravo with all six axes bound to something. 
In this sim it is the 172 and 208.
Almost exclusively a VFR flyer using the smaller airfields so I go for the slower, high wing types with uninterrupted view through the windows.
Recently been using the Blackbox BN-2 for the same reasons. The Max ceiling isn’t as good as the Caravan though.
Just like in real life, the C152.
I started with the Cessna 152 then went to the C172 for a while. I then jumped to the TBM 930 and now I am really enjoying the C700 Longitude. Quite fun learning different planes and all that goes into trying to become proficient at flying them.