Similar got mentioned here: Jump Drive Spool
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.