I think BitShares will definitely benefit hiring one more front-end developer.
I see the following areas where you can apply your skills:
1. BitShares wallet gui
https://github.com/cryptonomex/graphene-ui 2. Faucet software
https://github.com/cryptonomex/faucetFor #1 you need to be familiar with React.js. The objective here is to develop Exchange UI similar to ones centralized exchanges have.
If you want to go this route I suggest you to tackle one or more issues from this list
https://github.com/cryptonomex/graphene-ui/issues, just pick something simple - you need something to show to community to bring more attention, after that post your worker proposal here and on blockchain and let community vote.
For #2 - the Faucet is written in Ruby On Rails, so it's a good fit for your skills. The main thing we didn't finish yet is ability to track referral codes so anyone can send referral code with some amount of any currency to a friend and friend doesn't need to have BitShares account for that. Basically this allows you to send BitAssets to any email or social network account.
What needs to be done for this is to port Xeroc's python BitShasres client to Ruby. I've started this work but didn't have a chance to finish, I can share with you what I already have.
Next milestone for the Faucet would be to allow Reddit tipping via referral codes.