I was just getting some fresh air outside a few moments ago when I thought of something. This "something" refers to stuff that happens near the end of the planet so if you haven't played the M4-78 Enhancement Project, I really wouldn't read this.
I understand the need to kill off Vash and she no extra lines that could enable here to be available anywhere else in the game. However, Kaah was seemingly killed off for simplicity's sake. What I was wondering: if the modders didn't want to have Kaah show up anywhere else in the game, why not have the option to make KAAH the Colonist and have him stay on M4-78 to supervise the planet. (Presumably he'd be there until the Republic colonists arrive later and/or droid army was finished.) You just would have to add a dialogue option insisting that he countermand the orders to kill him - likely related to Intelligence stats. Then rather than suggesting he join you on your ship, suggest that since he's soon good at computers why not look after the colony? If you failed the Persuade role, he'd decide to get in his own ship and he'd fly off.
If you wanted those good old Dark Side points instead, you could have the option of intentionally not reminding him that M4-78's orders to kill him were never rescinded. Then he dies as usual.
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