OP, I am also a SRAM advocate. I haven't ridden Force but have both Red and Rival. If you can't afford straight Red, rather than going with one of the full lower groups, I recommend mixing the two or even three groups as well as 3rd party parts to get the best combination of low weight and savings. For example I ride only the Red cassette even on the Rival setup. Similarly I go with the FSA SLK Light crank to give me the weight of the Red crank at a much reduced price. I also use only the KMC X 10 SL chain for weight savings and reduction of noise compared to any SRAM chain. You can investigate the current pricing and weights of the three levels of brifters and brake calipers to see where you want to come down on those. The Rival or Force derailleurs (for 10 speed or Force for 11 speed) are plenty good enough. I know it is not as neat and clean as a full group of one model, but you can enhance performance and still save money and weight by this strategy. The Frankengroup you assemble this way is very high performing and cost effective.