Are there other technologies better suited to this purpose?
That's incredibly vague. There's a couple of ways to look at it:
Is WebGL capable of doing the walkthrough as you described?
Absolutely.
Are there low level 3D APIs that are better geared towards rendering home walkthroughs?
No. Every low-level option for displaying 3D content on
the web (WebGL, Silverlight, Stage 3D) is going to have roughly the same capabilities. They all
render triangles using shaders. Decisions about tech at this level are
based on other factors: What languages are you comfortable programming
in? What are your target platforms? Do you need to interoperate with
any other libraries? Do you have legacy code you are trying to make use of? etc.
Are there high level 3D APIs that will make it easier to render home walkthroughs?
WebGL has many frameworks that abstract away some of
the complexity of the API. ThreeJS is the most commonly used one, but
there are plenty of others. Your choice here should be primarily about which parts of the API do you want handled for you? (Mesh formats? Camera handling? Lighting and material systems?) If you want to look beyond WebGL then it's worth looking at Unity for a very complete scene management system with great tools. I would guess that Stage 3D and friends have some high-level support as well, but I'm not familiar enough with their ecosystems to say.
Are there any existing software packages that will render a home and fly though it?
For the web? Not that I know of.
If you have questions about any of those specific topics, feel free to ask.