Ive seen diagrams of what you mentioned first. Instead of creating choas it just makes a continuous loop. Ive even seen one where a person goes back in time twice, alters 2 pasts and becomes their own mother (when they started as a man). That made sense too (following the diagram). But by changing 1 thing it must form alternate universes. I hate to mention it but dragon ball z utilizes that theory w/ the androids (if youve seen it you know what Im talking about)
I think given the reality of time travel you would be able to meet yourself. Things like destruction of the universe (ie back the the future rules) probably arent likely since you and....you...are just matter. It doesnt matter what it comes in contact with. At least thats my take. After all, how would the universe know youre you and that youre special? Its not like something follows you around and says "you cant do this, this, and this."
Future travel probably cant exist because it hasnt happened. What we do creates it and anything at anytime can alter that. Its not predetermined like the past is....was...whatever. I have not seen anything about forward time travel, only returning to point of origin stuff. (point B to A and back to B...no C).
All of the things Ive read on time travel utilize controlling of either super gravity, fusion and electromagnetic reactions on dark matter, and wormholes - since all have effects on time, light, and everything else (theoretically). Basically what Okaku says is once we can control fusion on earth we can figure the rest out pretty quickly since its all based on getting enough energy.
Personally Ive become interested on photon behavior since it can travel though any material and doesnt seem to be effected by any of the 3 powers (gravity (since we cant get enough here), electricity, magnets). Its a fusion by-product. I wonder what would happen if we were able to harness it w/ super-gravity? Or large enough harmonic resonators (like how we can control minute amounts of fission reactions (the hope of fusion power here right now). Photon beams maybe?

Just a thought. Photon beams would just travel through it w/o effects imo.