Both the Phantom and the Defender have been avoided to date. The former has a cloak, a mechanic that we haven't attempted to deal with it, and the latter is a super-fighter, which, in order to faithfully represent, has to be OP, and costed to match. I would imagine when we finally build it (the Defender), it will be fairly similar to the ARC-170, extremely powerful, but also extremely expensive. Offhand I'd say you're looking at a 14-15 pt squadron, non-unique, packing along the lines of Speed 4, Hull 5, AS 2B2K+, Battery K, and potentially Escort for good measure.
For the Phantom, I did have an idea after seeing your request which is as follows:
Hull: 3
Speed: 3
AS: 3B
Battery: B
Cloak: If you have not attacked yet this round, you do not affect enemy squadrons and enemy ships and squadrons cannot fire on you.
Cost: At least 13
The astute commander will note that this wording allows a Phantom as part of a fleet with more squadrons than its opponent to never be attacked except by Counter. The even more astute commander will also note that this fighter, in doing so, cannot engage bombers, the traditional TIE role, only attack them, and cannot use Squadron Command except to move, wasting (in my opinion anyway) the entire point of a Squadron Command. You are welcome to try this, although I expect it may need a fair bit more work. This also isn't a rule easily applied to a full starship attempting to cloak, but we shall see.
Also, that cloak action means that if your opponent has few fighters than you, you basically have a free black die battery you get to fly around the board and ships can't scare it off with their antisquadron armaments, or lock them down with fighters. In oherwords the cloak action takes the current rules for fighters and breaks them in half.