Roller tip rockers are good for reducing friction and that's going to show up under your right foot, and also in longevity. That is, of course, provided that you get -good-ones. They are more complex, having more parts, and having one of the roller tips come apart on you isn't super cool wonderful for your engine's welfare. Just that one modification alone isn't likely to make enough difference to show on a time slip. Personally, I'd probably never use the rockers that have just roller tips but still e employ the factory style rocker balls at the pivot point. I'd use full rollers instead.
Timing chain is another topic -- you definitely want to nuke the plastic toothed cam gear if you still have that and go with a solid steel gear. Othern' that, I've recently read an article/opinion where the position taken was that the double roller chains will actually stretch more than the factory style chains/gears with the wide teeth. I am running a double roller in the Beast, but whenever it's time for a rebuild I'll definitely look into the topic a little deeper before I decide. One advantage might be that usually double roller sets are available that permit easily advancing/retarding the cam to several different settings, but you can accomplish the same thing with the factory style gear sets through the use of offset keys.
My usual response to 'is it worth it' questions is to say that it depends on whether you think the benefit justifies the cost - and that's up to you.
Engine color should be whatever is right for the year of the car. I love the Pontiac Metallic blue engine color myself... Eastwood has it in a 2k ceramic formulation and that's what I used on the Beast.
I hear you on the tranny.... I've got an extra TH400 in my garage that I'm going to go through myself "someday" just so I can learn about them.
Glad to hear that things are coming along for you