Well I'll step out of the ring for UI/UX.
But for anyone who's interested heres some inspiration to draw from...
Leading bounty sites
Nice to have features
- Leader board
- Language / Skill tags on posts
- Submission Count
- Order bounties by time remaining / bounty value
- It would be nice if those who have claimed bounties / submitted solutions to have gain some type of reputation for thier benefit and the benefit of those posting bounties.