Farm the patrol missions on mars. Farming patrols is by far the fastest way to rep. The best rep from a strike is from level 24 strikes which take about 30 mins. You can finish the same amount of rep from patrols in just under 10 minutes. I enjoy mars the most because it open and fun to scoot around on.
Also I bought my legs,arms,chest. I got have gotten Helm, and 2 weapon legendarys from actual drops. I have gotten a lot of stuff that wasnt for titans however and have broken it down to mats.
Picture of me farming Engrams.