I think this strikerless system we've been playing is a reactive solution, not a proactive one. We're somehow going to win the league without really playing a top striker for most of the season because we have the greatest tactician in the history of the sport at the helm. But ideally we'd have a top striker getting the goals- it's in Pep's nature to use one (Villa, Lewandowski, Agüero have all thrived under him).
To me, playing with no striker has worked out because of a mixture of Pep's ability and some great individual performances (mainly Gundogan. Fuck knows where we'd be if he hadn't stepped up). But I don't think it's going to be a long-term answer.