The new frame has a half a centimetre longer top tube AND a 1 degree more relaxed seat tube angle. This adds up and is what I would expect to see between two frames which were pretty much the same but with a different seat tube angle. Personally I think the new frame will be better. The more relaxed seat tube angle will take some weight off your hands and shoulders.

If you really want to you could push the seat forwards slightly on the new frame so that the seat would be in the same position as on your existing frame but honestly I would try first with the seat set back first.

Anthony