All games have their strong points. RoF is the "flight models", OFF is it's "campaign" and FE/FE2 is it's "modability".
I currently have four different FE2 theaters, Western Front, Eastern Front, Italian Front and Middle Eastern Front, while RoF and OFF only have one each. Also my FE2 Western Front has over 200 different planes or variations, and more are being made all the time. With RoF or OFF, you only have what the Devs allow you to have, not what the rest of the community can contribute. It is easy to add new items, planes, terrains to FE2, you just have to read the SF1/SF2 Knowledge Bases and understand where all the new stuff goes.
I use a TrackIR 4, so a TrackIR 5 should work with no problems too.