Due to busy flights over the Chinese New Year I'm finding it tricky to confirm a seat from Phuket to KL. I've heard there is a ferry to Penang, wondered if anyone had any suggestions for completing the trip quickly as I have an international flight ot catch out of KL.

You could try doing HKT - Singapore then Sinagore to KL. More expensive and a bit more time, but they are both heavier route with more planes and possibly more seats available. HKT to KL is not the greatest and it only runs a couple of days per week.