Sounds like a good combination Ids.
I have a Steve Woodhead Mug which is quick and easy, I fill the sink with hot water dunk the mug in the sink and leave it there while I shower. By the time I am ready to shave the mug has absorbed enough heat for a normal weekday two pass shave. I also have a Dirty Bird 1.5 Scuttle, this holds a good volume of water and is for the more leisurely days, I have to watch I do not overheat it as this destroys most lathers but it is good at making lots of lather, fantastic with creams and big brushes. In theory the ridged pattern should make no difference but I enjoy using this scuttle, nothing seems to make lather quite like it..
The last one I use is a brush scuttle, this is great for both face lathering and shaving in the shower. With no need for a lather bowl (although I have a small matching one) this heats the brush right through to the core and and the drying effect of the heat is negligible as the brush is bunged in the conical inner scuttle like a plug; if necessary I drip a few drops into the pot to keep the mix loose enough.
Over time I have came to the conclusion that scuttles are more useful if you have a cold bathroom, in the harsh winter there is nothing worse than taking a cold brush to your face. However in today's age of comfort living in the winter I sit around in my shorts and eat ice cream, most houses have an efficient central heating system with a timer, so when I get up for work the bathroom is toasty warm, probably warmer than it is in the summer. The warm lather or brush is just a nice to have than an essential item.
Really anything will do the job, for the first few years I used a big cappuccino mug but the scuttles and bowls are both functional and nice to look at. It is a difficult choice if you have never tired a scuttle, but your idea of a dual purpose item sound like a good middle ground; I would be interested to see a picture when you get it.