Yes to get JumpGate by t120 isent hard, the reason to lower the cost to tech it was to make population migration less painfull erly in the game cos you wouldent have any good engines.
Jumpgate doesn't allow population to travel faster, only military ships
And if you would focus on engine tech when reserching hunting it then you would severly cripple your defensive power and offencive power meaning that your opponent could split up his fleet to defend and then retaliate and overrun you.
Sure in late game the situation will araise again, but by that time the game would probly already be over or you would have several fleets.
Possibly, however didn't you think game could become enormously defensive?
About that outpost argument, it's not viable as I would move my whole fleet together with the outposts and as I would move between the planets (systems?)in 1turn you still wont know wich planet i will build my tripple outpost on and would have to guess wich brings us to the same issue again.
Your sentence is not clear...If I see many outpost flying in certain direction, this would be a clear sign that you are planning an invasion. I will have scouts in all systems you can arrive to and you inevitably hit my scouts, this way I see your fleet.
Have anyone eavent tried to see the result of this in game, bump up the engine teches 4steps or so in the tree?
No, but I have an idea for engines, thanks to our discussion
Imo the warp iredicator does the wrong thing to address this issue, as it only limits the fligt to your planets and not between all planets. I favor the engine /jump gate solution that slow downs your travel to all but your own planets.
On the contrary, warp interdictors is uber defensive tech meant exactly for this purpose. It can be countered partly only by hyperspace communications used together with thorium fuel cells.