IMO, stick with biscuit on sink and toilet.

Sorry but that tub is in no way a soaker tub . I have a soaker it is 19" deep and honestly cast iron is great I guess but since you are changing everything else whay not change the tub and be done I have been using Maax acrylic tubs for years I love them easy to clean come in that 19" soaker style easy to install and then all the fixtures can be white and not a dated color.

you have a few options.

Cast iron is better because it holds the hot water longer.

But, you're stuck w/the biscuit color. You could get an epoxy coating, but those only last a few years before chipping.

you could see about getting that current tub completety stripped and recoated the orignal way. it will cost more, but you'll have a white cast iron tub that will last another 50 years.

You could purchase another white cast iron tub.

you could remove it and do an acrylic tub that is deeper.

I would do white toilet since it's far enough away.

You could also do a wainscot skirt around the outside of the tub and hide most of the biscuit color.

https://www.addicted2decorating.com/diy-tub-skirt-decorative-side-panel-for-a-standard-apron-side-soaking-tub.html

as for tile choice, there are a million. just depends on the design you want. (A matte black tile like Bedrosians Makoto would be pretty above the biscuit tub)

the one thing I regretted when redoing my bathroom was not getting a new tub. Now I'm stuck w/this one until I redo the tile surround.

I had biscuit in my last house. It's not a bad color - it's not like the almond of yesteryear. It's a pretty subtle off white. So if you end up keeping the tub I don't think it's the end of the world. However, you will have to look at tile that goes with that warmer color. Some colors that would go with white won't look as good with biscuit.

You might as well get the biscuit toilet and sink, they make them, they are available, and it's possible the sink, especially if you get cast iron, could last another 50 years.

The house I grew up in had four bathrooms and two of the toilets were 40 plus years old and the other two were only replaced because my mother needed a higher one. It's not like toilets need to be replaced every 5 years.

Why start out with a non matching toilet if you don't have to?, it makes no sense. It's off white. It's not like you are trying to match an old green tub with something.

You may end up with a non matching one down the road if they stop making biscuit, but there's no reason to intentionally start out with a mismatch.

there really isn't that much of a diff. the biscuit is a little shadier. since the tub is enclosed and not visibly open to the tub, I really don't think a white toilet is going to be the end of the world.

There are diff shades of whites though. maybe don't get a super bright white.

And like I said, a tub skirt can be made to hide the majority of the tub color.

But if you plan on doing warm, natural tan colors, wood vanity, then by all means, do the biscuit toilet.

It has a 13” depth to the overflow which is pretty good for a kids bathroom.

These are all very good points. I think I need to figure out what tile look we want to decide whether to just go with acrylic, another cast iron, or keep this. I really appreciate it.

I like it. I so miss my cast iron tubs. I’d get a biscuit toilet, but the sink/vanity could be more creative.

Check out Heidi Caillier’s IG — she’s a very talented designer who uses a lot of tans and warm, earthy tones in her rooms (with other colors). It might provide inspiration. I love her designs. There are lots of other designers going in that direction now, too.

It’s not like it’s magenta or diaper contents brown … it’s a very subtle neutral color that could look great with lots of things. You’ll be ahead of the curve (trend). :)

FWIW, I have a 32x66" Kohler Bellwether tub that we got new a couple years ago and it did not require a longer tub spout length. IIRC, the tub spout length issue was a thing more than 8 years ago and the Bellwether style changed slightly since then. But maybe I'm remembering wrong?

Biscuit is a normal, neutral color though so if you want to keep the tub, keep the tub. I would personally go with biscuit sink and toilet too. I just haven't heard about the Bellwether still requiring a longer tub spout length so that part of your post caught my eye.

I have a Bellwether too and mine did not require a longer filler either. But they're not that hard to find. I think the finish on your older tub is probably superior to what you would get now. Cast iron has gotten a little rippled and it's not considered a manufacturing defect.

American Standard has Americast tubs which are not cast iron but are supposed to be a sturdy metal lighter weight alternative to cast iron. This is what I was considering until the price went up and my budget went down.

https://www.build.com/american-standard-2461-002/s132305

If you really want white (I would) you could consider the Cambridge which has soaking depth.

You can call American Standard and talk to a manufacturer agent about the technology if you want.

Do not give up a good cast iron tub. Off white toilets and sinks are easy to find.

It's a KIDS bath. Get a new tub! Kids and even the occasional guest will never know the difference. You will. White is the cleanest ,brightest fresh slate you can ask of a space in fixtures. Just rip the tub.