Rating Problem
I have played with people rated as 1500 whose performance says they should be 800. The reverse is also true with some 800s playing like 1500s. Hence the current scoring system doesn't tell you how good your opponents are.
Benchmarking Tools
I think a better way of evaluating a players skill could be determined by some or all of the following:
1. The average time it takes to reach a score of 100,000 during games. (Averages minimise the impact of occasional assasinations in early and mid game on score).
2. The average time it takes to reach a certain economic output during games.
3. The average number of acu kills they get per game.
4. Their win and loss ratios for the map whose game lobby they are in.
5. On average how much mass and energy they reclaim per game.
It will not only lead to more balanced games but with people being measured against those things they will improve in those areas (hopefully!). Any chance of something like this being introduced?