Ok, I think I answered parts of both of my questions, but still need some help:
1. It looks like Cufon is always associated with some kind of page element like p or h1 or cite. I tried on another page to use a subclass specified in custom.css like h2.ital which specifies italics, but it had no different effect than using the em tag. Is this the right direction to pursue? Is it a load order or something that's the problem, and to fix it do I need to define an entirely different class or else subclass in your Avia code? I'm using a child theme, so please let me know, I don't want to break any code if you update
2. I'm not sure how to address the second problem, but perhaps it's something you could add to the theme as an update? This is what I found online regarding delay... it also happens with Firefox on Windows:
In IE, there will be a short but noticeable delay between the old font being flashed and the new font replacing it. To fix this (optional), add the following line of code just before the closing <body> tag.