I've started to make a mod.

[Suicide Junkie]

#1: Make it FUN for YOU.
#2: Make it balanced where possible, so at any one point in the game, you can do things more than one way and still stand a good chance.

Check out some of the existing ideas floating around and figure out what set of them strikes you as "The way of the Future", and then add some unique stuff that appeals to you as well.

If you're not sure how to go about implementing something, just ask! One of the modders here will be able to give you suggestions on how make it work, and point out any pitfalls you need to beware of.