I don't think he should have done any time for the drug-related charges. And 10 years is more than enough for a murder-for-hire in which nobody got hurt. So this seems... just.
But in Ulbricht's case I'd say even this part is mitigated by the fact that facilitating the trade of dangerous drugs was a side effect of running a useful service for responsible drug users.
What if they sell things that aren't what they say they are and the user dies or is hurt?