Currently there are 2 viable teleport upgrades in the game: Cybran and Seraphim. Both rely on late game snipes focused on air grids or ACUs. Aeon and UEF on the otherhand, currently suffer from clown upgrade syndrome with regards to their teleport and I literally have never seen either faction make this upgrade except to troll games by teleporting ACU around in water.
I've got 2 main ideas for how to make these factions more viable. The first two proposals will be for UEF and the third will be for Aeon, but the idea behind the proposals are similar.
There are two ways to make UEF tele not a clown upgrade, far as I can see.
Proposal 1: [UEF] Move the Upgrade
The first is to keep the upgrade the same and put it on the right arm so you can do a T3/Billy/Teleport ACU.
I've heard people say this is OP, which I think is patently ridiculous. You need 560 mass in TMD to actually stop a billy (if you're not Aeon) for a wide breadth of range. I would wager an air grid could be protected by like 3000 mass in TMD total. That's like 10 TMD. Not to mention, it's incredibly easy to emergency build 2 TMD to shoot down a billy compared to the respective counter against Cybran or Sera which will require a decent setup of hives and shields at a minimum.
You need approx 10 or so t2 PD to actually dissuade a Sera or Cybran teleport which comes up to around double that mass cost in TMD. Beyond that, a billy requires payment for each missile and if the first one misses, the ACU isn't accomplishing anything for the next FORTY seconds as the missile builds. A Cybran or Sera ACU can always teleport to a new location or walk around outside of PD range to get more value. They also can outrange T1 PD defenses if they actually got gun upgrade.
However, even with all those negatives, a teleport billy allows you to be more aggressive in getting good shots against unit mixes or unprotected bases. For that, it should still require the default teleport cost.
Proposal 2: [UEF] Cheapen the Upgrade
The second is to make teleport a two t3 pgen cost item or so as then it could allow UEF to have a period of time to actually make use of a t3 ACU proxy base teleport. If the upgrade is kept on the back, there is zero tools for the UEF ACU to utilize aside from their T3 suite.
Therefore I propose:
Mass Cost: 15,000 -> 5,000
Energy Cost: 1,500,000 -> 500,000
This means that a T3 ACU will be getting the upgrade for about 110 mass a second, 11,250 energy a second, and for 45 seconds. Effectively, it becomes viable around a t3 pgen later than Cybran or Sera late game ACU upgrades.
These costs seem reasonable as the e cost gates it to the time periods you need to worry about these sort of cheese upgrades and the mass cost is around what you would need to actually make use of a T3 ACU teleporting around the map.
Proposal 3: [Aeon] Do Both
Move Aeon Teleport to the right arm so that you can do:
I don't PERSONALLY think any of these combos are insane, but I'm open to Aeon keeping their teleport on their middle so you can't give the extra HP of shield on the teleporting ACU if people think that's OP. I think, cost wise, there is no real reason for UEF or Aeon to differ if that's the way UEF goes because the main threat in either faction is the T3 suite.