If you could post more pics of the room, that would help--not being able to see more makes it hard to judge if it is original...such designs are still popular and could be part of the later renovation.
Your tile choice looks good as a match, and if the floor is as good elsewhere, it is well worth saving. If it is original, it will be hell to remove due to the method of installation--not thinset mortar over subflooring like is done today--those were put down with a thick layer of cement and mortar which would likely resist all but a jackhammer to get out! :)
My own bathroom floor in 1908 was wood, then around 1967, that was covered with newspaper, two layers of painted hardboard, and finally carpet! I ripped it down to the original when I moved in in 1987. The real luck was that they didn't bother to remove any of the fixtures, so I have my original clawfoot tub, commode and wall-hung sink!
Post some more pics of the room if you can!

I think it sounds like a good idea if there are no condition problems.

The colors of the original are quite nice, imo. So I would follow your plan. Of course this is one of those projects that could turn out to be much bigger than expected. I would try it anyway!
Diane

I took more pictures of the bathroom as it is right now so you can see what I'm dealing with. One of the maroon tiles on the shower wall fell off and cracked, so between that and the toilet repairs was what got me thinking it's time. Also if you notice the outlet on the vanity/light fixture that's not GFI so that will need to get updated and the ventilation fan I would really like to move to the ceiling where it belongs.

Here are some more pics (sorry about the cell pics, I still haven't found what my kids did with the regular camera):
http://i521.photobucket.com/albums/w339/katmu_album/554168170_1962722423_534196955_1280890895094jpeg.jpg

http://i521.photobucket.com/albums/w339/katmu_album/554168345_1962723058_534197136_1280890864668jpeg.jpg

http://i521.photobucket.com/albums/w339/katmu_album/554168596_1962723992_534197400_1280890833754jpeg.jpg

http://i521.photobucket.com/albums/w339/katmu_album/554168035_1962721928_534196821_1280890916639jpeg.jpg

Moved all of the pics into 1 folder:

Here is a link that might be useful: Pics of current bathroom

I would make the changes you have suggested keeping as much of the original tile as possible, and adding the matching tile as needed.

I have mixed feelings about reglazing the tub: we had it done and it failed within a few months. I know some people have had success with it. Even when it was first done, however, it felt "painted" to me. Once it started to really fail, I stripped it all off and lived with the tub in original condition until the entire bathroom was renovated. (I had a 1965 bath, nothing interesting or "vintage" about it, unlike yours.)

The bathtub is actually the piece I'm most worried about. There is really only one spot that needs to be repaired, so I've been back and forth on it. I would absolutely replace if I could find another cast iron tub that deep.

I am worried that even if you found a tub, getting that one out would destroy a lot of tile around the tub area and the floor next to the tub. This was why we tried glazing first. They had to tear out the wall (and part of the floor although then we tore it all out anyway) to get the old tub out when we bit the bullet and renovated.

I'm going to try the reglazing. I just can't bear to rip out that tub right now. Hopefully since soon it will be just me and the dog that it will hold up. (And during the warmer months, the dog really prefers to take her baths outside in her doggie pool.)

I found a local place that can replicate the decorative border tiles. It would be $350 to make the custom mold and then $22 each for the tiles. Worth it?

How many do you need?

Worst case scenario would be 22 tiles @$22 each or $834 total including the $350 cost to make the mold. If I can get some of the existing off the tub area without breaking them it would be less.

Just curious what you ended up doing about the tub. I'm pretty sure that we have the exact same tub in our home (1925) and while I absolutely love the design, there is a lot of wear and tear to it. If you did end up taking it out, were you able to find a similar replacement?