The niche space in the upper right corner of your drawing looks like it would make a good play area. Exercise / elliptical could be either be in the corner directly opposite the play area niche, or in the space to the right of the post. Entertainment could be the area to the left of the post. (That might be best with the elliptical to the right of the post.). Perhaps the back of the sofa could be a boundary between entertainment and elliptical, and to block the few feet from the post to the wall at the bottom. The shallow niche(?) along the left wall could be TV location. Play area could have kid accessible shelving for books, games, craft materials — perhaps on the back wall of that niche. Craft table just outside the niche. Playhouse in general area. Perhaps some jacket or towel hooks on the wall near elliptical. Beanbag or big floor pillows shared between the play and entertainment areas. (Possibly appreciated by adults after workouts.) Just my 2 cents. Try measuring the things you want to have in the space, then cut out bit of paper to same scale as the room. So much easier to move around paper things than the real ones. As you find possible layouts, take a photo for future reference. Do the same with things that don’t feel quite right. That can be instructive too.
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Mudroom
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