Oh great! You knew I wanted to "talk" didn't you?
I like to stay in the 7th so here is a suggestion for a couple of hours walk on your first afternoon. What I'd do from the Duquesne Eiffel is walk to the Champ de Mars across from the Ecole Militaire (Napoleon went to Military School here!). Walk down thru the Champ de Mars to the Eiffel Tower. (Ignore any people who ask you if you speak English, don't sign or acknowledge anyone with a clipboard. Do stop and look at the kids having pony rides and go karts!) Go around to one side, then if you have the energy, cross the street and river and walk up the steps to the terrace at the Trocadero for the view. Walk back down, cross back across the river, and then descend to the river level and walk along the quai to the first stairs to come back up to street level. Walk in front of the Museum du Quai Branley and take a right on Avenue Rapp. At this corner is a Russian Orthodox church which is open sometimes. I'd actually never noted it was Russian Orthodox until this last visit. Walk down Avenue Rapp to #29 Avenue Rapp which is a fantastic facade by Art Nouveau designer Jules Lavirotte. You'll see it better if you are walking along the west side of the street but you can cross back and forth, lol.
After this, walk a few more feet and take a left into Square Rapp for another building by Lavirotte.
Back on Avenue Rapp, Continue to the complex 5 point corner and take a left on Rue Saint-Dominique. Walk along here about 2 blocks (going past the street that Hotel Londres Eiffel is on) to Rue de l'Exposition. I picked up from a Corey Frye video walk thru this area that there is a plaque on the fountain here that says "Crue, then there is a line and then Janvier 1910". This is the line of where the flood waters rose from the Seine in the big flood of 1910. You will have walked up this distance from the river and it is very hard to believe the river water came up this high!
From here follow the route down Rue l'Exposition to Rue de Grenelle and east to Rue Cler, then up Rue Cler to Avenue de la Motte-Picquet. Take that to the right and over a block to the corner where La Terrasse Restaurant is (and you'll see the Ecole Militaire metro stop) and take a left to go back home.
The walk from the Lavirotte buildings down thru Rue Cler is on Corey's walk thru the 7th.
If you have extra energy you can also add in some of his walk in the Trocadero area to see the original palace pieces from the Tuileries Palace and see a little grotto area.
To do that when you cross over from Eiffel Tower toward Trocadero on this map you'd cross Pont d'Iena and angle off to the left by the carousel along Avenue des Nations Unies (really you'd walk the sidewalks thru the park area), then hit the corner of the small street on the west side of the park area. At the corner is the little grotto area he shows and the palace pieces are along that small street toward the end of Musee de l'Homme. You can cut back across the paths to the central esplanade area for a great Eiffel Tower View.
How much you add or subtract will depend on how much energy you have! Easy to delete some and head back home. The things I particularly like to see my first day are the ET and the Lavirotte buildings.
This is a wonderful tour - really will make you love Paris. Unfortunately it has created an addiction for me, hahaha!