Technically, the HTML spec says that attributes for HTML tags should be name-value pairs with the value quoted. Reducing the size of your generated HTML is admirable, but how you're trying to do it will not gain you any signifigant savings.
| String | Length |
| <font face="arial, helvetica, verdana"> | 40 |
| <font face=arial, helvetica, verdana> | 35 |
| Savings | 12.5% |
When you consider there are still the end tag and whatever was inside the font tag, your savings goes down even further.
In summary, I would spend most of my effort on a clean design and layout of the webpages, and let the tags fall as they may.