Come on, you're a medical student too. You should know better than that.
Try this: "I've only flown economy a few times (twice on long haul) but it seems to me that with more and more people flying long distances, economy class is just too dangerous. You never know when DVT might develop -- and just moving around the cabin isn't always enough. This is particularly true for elderly people who have trouble ambulating. "Move your legs" might be good enough if you're flying LAX-SFO or something, but I honestly think it's no longer good enough for flying LAX-SYD, or similar long trips. Maybe they should start dispensing coumadin for all passengers."
You may "honestly beleive" your opinion, but based on what? You're not a pilot, for one. For another, mid-air collisions between GA airplanes represent a vanishingly small portion of GA risk. From 1991-1999, there were 3245 fatal GA accidents of which 78 were midair collisions. That's 2.5% of GA accidents, or about one per month.
As for additional ATC control or TCAS helping, from where will that money come? Even if you think it's worth spending, the $$ available is finite and will come out another budget, flight school or ATC, that could be spent more effectively to reduce risk. Furthermore,
half of midairs are in traffic patterns, most of which are pretty well controlled already in Southern California, and are so congested that TCAS would be of little use.
I agree with you that these collisions are tragic, and that ways to avoid them should be sought. But please don't wildly suggest expensive, impractical and onerous solutions to a problem you don't really understand.
Stats from AOPA Nall report 2000