It's not hard to get the weekly cap of 100 marks for both vanguard and crucible also doing the daily bounties and ranking up your vanguard rank to 3 and above gives you a package which has a chance for gear although it's a random class. I got to 26 on my warlock and hunter because I already found legendary gear by grinding with my Titan and at 26 I was able to do vault of glass and at 27 I did crota albeit I was carried through crota but it's easy to solo the lamps with the blade dancer class aswell as patience and time.