Well firstly your logo is bad. I personally look at the logo as one of the first things, and it does a lot to persuade my view as to the value of the actual site itself.
Also, there are many sites like that on the internet as you mentioned, and to get a site where people actually pay you money, especially when you're not selling something outright, but allowing them to bid, is hard. People have a lot of skepticism nowadays about sites like that.
So, as the site itself, I doubt strongly you'll be able to build it unless you have great resources to invest already. If so, it may be worth investing in, as the domain is good, but the better thing to do in my opinion is to sell the domains, as they are good keywords.
The point being that one who invests in these types of things in the age post-ebay, requires a lot of $$ to establish brand trust and brand awareness, with the focus needing to be on the former, but to which the latter does add.
I also think it may be better if you increase the max bid increment to more than a penny, lest you be ripped off by snipers
If you are offering your own inventory especially, tehre is huge potential for failure here, which is why I devalued the name + the site as opposed to just the domain name.
If it were me I would thank my lucky stars I got such a good domain name, I would recognize I have no where near the resources to pull this sort of thing off, put it up for sale, and hope that something I'm very interested in comes my way that I do have the resources to develop.
Don't be surprised if you get a low $$$$ offer as well. Its a pretty good name, and the fact you've got the package of two of the most recognizable TLDs to two of the biggest markets (the world, and the UK, lol) makes it worth even more.
Good luck
