My take is the following:
Give all Capital Vessels a flat 10 second Spool Up Timer that charges the JumpEngine.
The Spool Up can be canceled on the pilots choice or when being pointed/bubbled as usual.
Spooling Up cancels any InvulTimers.
The change will make fielding Capitals slightly to a lot more dangerous in certain situations when catchend in surprise.
Titans miss clicking the Jump Command have a short opportunity to cancel their mistake in making.
Jump Freighter Logistics get a lot more annoying with this change thought which either need to be an exception or getting a reduction.
Jumping a capital from a camped station or structure is going to be impossible.
Have a capital ship in an asset safety station? Consider it gone.
Jumping your capital from one station to a cyno on the next while there are enemies in local? Not possible unless you have immediate backup to escalate.
harder, I saw no one stop me jumping out my capitals from Irmalin.
And with no InvulTimer I mean the one after falling out of warp or after jumping. You can still be Tethered while jumping from a Citadel and if your POS is bubbled you were unable to jump away from it anyway already.
Not every citadel has tether and NPC stations don’t have tether at all.
And the current situation is not accurate for how the situation is going to be if such a spool up to jumps would become reality. If people can get free capital ship kills by cloaking an interdictor at the undock of an NPC station, they will.
Pretty sure you can still dock on normal stations while getting pointed /bubbled unlike Citadels.
Yes it would make moving solo a major annoyance when meeting some dedicated Station camper but with a bit of friendship one can solve that.