the biggest reason to goto 433 aside from having absolute control no matter what you fly behind is to open up 2.4 for video. The quality and difference is amazing.
The only problem with trackers is your counting on another system to work. naza with gps alot less problem, but none the less. I'm trying to get out of my tracker and go to all manual aimed stuff with diversity. Counting on a satelite connection to work is my biggest problem. my eagle tree likes to either not lock in or to loose connection randomly. took 30-40 flights, but the 5.8 video with 2.4 controll seems to hammer it worse than any other combo. Your flying along, notice junk on the screen, look over and the antenna is pointing the wrong way, look back at the osd and gps coords are gone, compass defaults north and the tracker freezes. EZosd trackers go back to default position unless my friend that had it sucked that bad, which he could.
You're saying the difference between 2.4 and 5.8 for vid is amazing? I haven't be left lacking on 5.8 vid yet, but I'll keep it in mind. The thing I like about 2.4 for control, obviously is it's dead-nuts simple, and cheap. And the FrSky stuff just seems to work. And I have telemetry on the radio link giving me bi-direction RSSI which is awesome.
I understand you wanting to keep it simple and get rid of the tracker. But, the Arducopter telemetry link seems to be pretty solid. I've never lost the link in the air, even a little bit, except for one time when the cable between the Xbee and the APM vibrated loose in my 4-stroke powered airplane, which was totally my fault. And then if I did lose the telemetry, I'm pretty sure the tracker system would just stay at the last known good position.
And even then, I have a failsafe. If it all goes to hell on the ground and I loose vid and/or telemetry and/or control and/or the tracker stops working... it will RTL pretty reliably. But I totally understand what you're saying, if you don't have RTL ability, you do not want to add another system which can fail, leaving you with no control or vid, when you're a mile away.
Terrain is just street.. No high buildings but lots of lots of objects like cars, trees, bushes, hedges, people, houses.. Everywhere there is an object that will cause reflection.
And this is causing you problems?
Where I did my 200m test is in my back yard, as shown in this vid:
http://www.youtube.com/watch?v=ZLerXsxkOf4&feature=g-upl
So the ground control is on my back deck, with the house at my back, other houses around, cars and streets around, bushes everywhere. That bush you see in the background goes back 200m. I flew up on top of that bush, and then back 200m and was hovering over another subdivision, with houses and trees and cars. No problem at all.