High tier techs?
I have some random ideas:
Mass production of antimatter (element based too). Antimatter fusion reactor. Heavier and denser antimatter elements are used to store energy.
An artificial dwarf star that produces sunlight-like light on a few chunks around it.Who needs lamps when you have your own star in your backyard.
A phase shifting device that allows us to go through objects (like 1.8 spectator mode noclip).
A click to teleport to where you're looking at device for quick transportation.
Mass destruction weapons that harnesses the power of antimatter.
More magitech items that uses TC magic. (voidmetal-naquadah alloy).
Magitech: Allow mass purification or taint of land using a machine.
Terraforming: A block that relies on UUM to change the biome around it to whatever the player chooses. This was supposed to be an IC2 feature but...