is it worth it? that depends upon you.
are you really doing all 4 parks, & dd? then you will need to bus (even from Polyn) for AK, DD and Studios. these buses are shared with other MK resorts.
you can take the boat to studios but that means entering Epcot and walking across Epcot to the boat. It also means you need a park hopper.
a one year old definitely needs more downtime than when you and your husband went alone.
can you cut back - if you only did MK and Epcot - then Polyn would be great.
that say if your favorite parks are Epcot and Studio - then one of the Epcot resorts might work better - BC is nice. the bc and polyn both have a character breakfast onsite.
now if you are going to go to all 4 parks & DD. remember DD is the worst except for SSR, OKW and PO. they have buses and boats to DD.
might see about OKW - it is cheaper than Polyn and you can have a little more room than in the POR. Plus it is at least a studio so it has a kitchennet.
there are several washers and dryers around the pools for your use for free - just remember to bring your detergent and fabric softener. Now the washers and dryers are free only to guest staying at OKW.
the one bedroom villa and up have a completely kitchen. This includes a washer/dryer in the villa. alot more room but it also costs more.
you can rent a reservation from a
DVC member - that will help kept costs down.
now there is BLT that you can also rent from a member - but it is expensive. You can walk to the MK (it and CR are the only resorts you can do this).
but if your only choices are the Polyn or POR - then might go with POR it is more centrally located.