This is the reason we own at BW and BLT and will do split stays every trip.
IMHO, the monorail is advantageous going to/from the MK and going to Epcot. However, the trip back from Epcot to the Cont is indeed a very long trip, especially after illuminations. (But another poster Had a GREAT suggestion that you can just walk over to the beach club (5 minute walk from inter'l gateway) and hop a bus to the MK. Or hop on the MK bus from the parking lot.
NO resort is perfect. As another poster pointed out the transportation is not very good from the BW (considering this is a deluxe). My kids & I watched wishes from Main St and left the MK at 10:10. We never got home to the BW until 11:00(because we stopped at the S/D & yc & bc before we got to the BW (in order to get home 20 minutes earlier we have to get off at the Swan and walk from there ---which is exhausting after being in the MK all day-- We also left the BW at 8:20 to go see wishes and never got to the MK until 9:00. So it does take a long time to get anywhere from the BW too.
However, the reason I bought at the BLT and am so excited about owning at the BLt is because of the monorail. After Wishes or at closing (now that the kids are getting older) we can just hop on the monorail and be home in 5 minutes!!! Yes, it will take 20 minutes to the Mk in the morning, unless we walk, but that the thrill of taking the monorail (to me anyways

) is that we get to stop at the Poly & GF to pick up on the way to the MK. Its just magical watching all the little kids get on so excited. I just think the monorail is just so cool, even if it takes longer to get there.
Just like nothing beat the boat on a beautiful breezy warm evening from Epcot or DS to the BW even though its a slowwww ride.
With the buses- well its just a bus and there can be extremely long waits especially at closing, and half the time you NEVER get a seat. Plus what kills me with the buses is all the traffic lights and turns. You don't get many traffic lights on the monorail

. Or you don't have to turn into 3 resorts and then go through the drop off and then get back on the street.
IMHO, I had the best bus service from the All Stars Sports.--- it was a straight shot to every park. That's what I'd expect from a deluxe but since we are in walking distance to 3 parks now-- I can't really complain.