I am building a 2 player, rebellion vs new order, outfit aside of my main xwing collection which I can take for a spin to friends. So far, I stocked up my Force Awakens trunk with: 3 tie/fo, 1 tie/sf, 1 Upsilon and on the other side 3 T70s and 1 Uwing ( i know its from rogue one, but i kinda like the idea to put a retro-uwing to pitch agains the new order ties. Ive got some nice squad builds out of this set (obviously using also upgrades from my main xwing collection) but definitely see that the dark side could use more ties for build options. Note: Im pretty straight forward with rebels, but somehow the new order simply begs for more options. Flying without Upsilon only allows me to fly a Tie/sf 3tie/fo list, no sec tie/fo list.... Sooo my question is, should i buy another tie/sf or tie/fo. The tie/sf would allow me to fly Upsilon with both of them. The tie/fo would allow me to fly an (heavily upgraded) tie/fo swarm. Importantly: i do not want to fly regular ties in my list! The challenge is really to complete my force awakens trunk, which unfortunately only allows me to buy one more tie... Im a mediocre player and a sucker for confined collection, so hence me putting restrictions on my buying frenzy :-)

Depends on what you want. Do you want to be able to throw a swarm at your opponent? You can do that with two basic S/Fs and three F/Os. You can also do it with four tricked out f/os. You also have to think of what you want for regular play. Do you ever see yourself using four f/os and/or a second copy of Juke or Comm Relay? If so, grab yourself that f/o. If you'd rather fly Backdraft/QuickDraw, or Upsilon/Specialist/Specialist, then go for the s/F.

Generally, I like to have at least two of each small ship. So I'd say pick up another TIE/sf to boost your options. That being said, there are some cool builds with what you have already. Here's one that I played recently:

Quickdraw (Rage, Electronic Baffle, Special Ops title, Shield Upgrade)

Zeta Squadron Pilot x2

Starkiller Base (Reinforced Deflector)

100 points

Yup, another /sf gets you Quickdraw and Backdraft with FCS, Targetting Synch, and Omega Leader which is a very strong first-order-only list.