Unfortunately entangled particles themselves have to obey the speed of light rule, yeah we could communicate instantly over vast distances with them but not until they have been distributed, which could take millions of years by any practical means.

Indeed the universe is meaningless without an observer but when a single photon that's been around since the beginning of time (or any other particle) counts as an observer there is no reason to think we are special in that respect and a crime is still a crime whether a judge "observes" it or not. It annoys me when people take the logic of Quantum Mechanics and apply it to the macro world, you cannot do the Schroedinger's cat experiment for real, that was the point of it.

As for quantum computers, don't worry, unlikely we could build anything that does not de-cohere before rendering anything other than trivial results. This is not a limit of our technology, it's the nature of the universe.