We're doing a totally new bathroom in a kooky space that's the bottom half of a split level room. So the bathroom is accessed by stairs that drop you into an internal normal-height area of 2.5m x 1.8m (or just under!).
This is the sunken middle part of the room (while floor isn't sunken because of foundations issue). So around this walkable area is mostly countertop height, from .5-1m on almost all sides.
Opposite the stairs is a fireplace that starts at the "countertop" level (ie the old floor level). We'd like the bath to go just in front of the fireplace - I'm not sure if we can get the fireplace actually functional, but it should look beautiful!
My big question is, what sort of bath to get? I'd LOVE a bath which:
- lets me soak myself properly, ideally easy to sink up to my neck as in normal-depth baths my shoulders and chest tend to get cold
- can be shared comfortably with DH or DC
- is ok for bathing kids (ie not TOO deep to lean over the side)
- is comfy (ie not head-cracking stone etc)
- doesn't cost the earth (so prob acrylic and nothing TOO fancy)
- no whirlpool features (have a thing about this)
Any ideas? Am interested by the Japanese soaking tub approach, especially as some keep the water hot??! 
But don't want it to take a age to fill or be so big I can't sit/lie comfortably or never bother using it... And things like armrests, raised bits etc just confuse me...help!