Font handling was improved in Xara Web Designer 9 (support for multi-weight otf fonts). I would like to see this expanded with full support for open-type font features. This seems particularly appropriate for the PRO version now that the OTF fonts are the standard, higher quality fonts are becoming available trough Google Fonts and single font weights available for free from commercial font foundries. This will give us access to features like:
Small Caps
All Small Caps
Case Sensitve Glyphs
Ligatures
Old Style Numerals
Old Style Tabular Numerals
Lining Numerals
Tabular Lining Numerals
Small Cap Numerals
Small Cap Tabular Numerals
Pre-Built Fractions
Stylistic Alternates
etc.

Hyphenation would be a good addition too.