If I were given the chance to reboot Star Trek, this is what I would do.

1. Concentrate on exploring new worlds instead of political squabbles within the Federation. Trek is in the title for a reason, after all.

2. Remove all the technobabble and bad science.

3. Make most of the human/rubber forehead aliens genetically engineered human offshoots instead of entirely different, unrelated species.

4. Redesign most of the human/rubber forehead aliens to look more alien. For example, I'd make purebred Vulcans taller, with longer faces, green skin, and V-shaped bone ridges on their foreheads.

5. Make the "rubber forehead" Klingons and the "human" Klingons two seperate species; the latter would serve as a genetically-modified subspecies of the former, created to serve as covert spies within the Federation.