1. You can create a realistic lightsaber mockup using plasma cutter technology. This saves a ton of time. Now, all we have to do is modify existing technology.
2. You can rig a display table to hide all the large components of a plasma cutter. Show it off in a museum, movie theater, or other experience. You can also place the components inside an animated robot.
3. If parts and fuel cannot be miniaturized small enough to fit in the handle, a hose can be connected to the handle with a chord designed to stay out of the way while practicing swordplay. (ex. Water Jet Pack- "FLY BOARD" http://www.zapata-racing.com/en/flyboard/). You can also checkout Tesla's snake adapter as a way to manage where the chord hangs in relation to your movements.
4. At 1st, there is no reason why 2 lightsabers would create enough friction to stop each other's trajectories because a Jedi would know, the best way to end a fight is fast and efficiently. It would be best if nothing could stop a lightsabers path. However, as a defense mechanism, the other lightsaber wielders would need theirs to stop the trajectory of their enemies attack. Plus as a swordplay training mechanism, skills can be developed when the sabers can interact.
5. Eyes. We would need to start with special eye shields and potentially custom clothes that the lenses are tuned to see better.