I wouldn't spend any money on a CPL conversion. There are only a few jobs for which a CPL will be beneficial, i.e. you will be the PIC of a CS-23 airplane, and those vacancies will most likely be filled by guys who have a couple of hundred hours more than you. Contrary to common believe, most business jets are CS-25 airplanes, so no advantage there either.
Try to keep your 737 rating current for two reasons: a) there's a good chance that one day you'll be assessed on 737 simulator and for that you should be on top of your game, after all you're type-rated on the airplane, and b) most training departments would like you to have a current ME/IR upon joining, even if it's not strictly necessary.