While I'd welcome a Bard class or something new to do around Tamriel, my number one ask in terms of features is definitely new weapons namely 3:

• Spears
• 1H + Destruction
• Crossbows

All three are present in mainline games and somewhat represented via skills but I'd like to see them fully realized as new weapon skill lines with scribable skills inserted in as well. They could help freshen up combat rotations and provide something new with light and heavy attacks. People are adverse to any changes to combat in fear that ZOS will make it worse so new weapon lines could try new things without changing what's already there. Instead of heavy attacks a spear long press could result in a combo of jabs, a fire ball in the 1H destruction could result in an AOE or a crowbow could fire in a horizontal line hitting multiple targets. They could experiment with ways to improving the impact of combat with hit stop on melee, reverberating magic on contact, etc.

For me this would have the best impact on the game affecting all of my characters say for one that a new class would provide.

There are a number of concerns with new weapons that have solutions:

• "You can't expect ZOS to go back and add style motifs to Spears/Crossbows" Agreed simply do the base races and then only do new styles moving forward. A legacy set would use the racial set the most closely represents it High Elf would be used for arms of relequen for example.
• "I don't want to grind old content just to get one weapon" I think this is a fair concern but sticker books alleviate this issue or ZOS could choose to give us spears if we unlocked greatswords in that set or something.