The flares and turret was just a rough example. Here are some of my sort of more thought out ones:
"Boxer" Heavy duty class: more HP if intercepted by a UFO, the main and side doors having medium cover attached to the doors, can carry vehicles/slower then other, uses more fuel, can't carry extra troops
"Valkyrie" Medical class: improves all healing done to troops who are inside the craft, increased chance the crew will survive a crash, decreases civilian casualties during missions and gives the civvies a chance to get knocked out instead of killed/less HP, can't carry vehicles or extra troops, uses more fuel
"Interloper" Interceptor class: Fastest dropship available and could do some good damage to UFOs, can attack and disable landed UFOs, lands closer to crashed UFOs/less HP, can't carry vehicles
"Red Army" Carrier: carries the most troops out of any dropship, can carry vehicles at the same time and extra troops but airdrops vehicles near the landing site instead of rolling out the craft/the slowest of all the craft and uses a lot of fuel
Still very basic but just to show the concept of it.