Define hoirrible, a CTR over 2% is considered good. Adcenter is a comparison engine so alot of the organic listings compete with PPC and I find that unless you're a big business Bing is not a nice place to advertise for some products.
Since a lot fewer people use Bing than Google and Yahoo, you can theoretically get a much better conversion rate than the other search engines. There's a lot less competition from other advertisers, so in my experience conversion rate and cost per conversion in AdCenter is comparatively very good. Expect to get a very low amount of total conversions, though.
You want to have more keywords with msn. Way more!!! Very little clicks from a lot of keywords adds up.
This is actually not usually the case. That's actually a quick way to lower your CTR. Here's what I would do: First, separate your keywords so you can track what each individual keywords CTR is. Second, split test your ad copy. If you are ranking in the Top 3 results and getting a bad CTR, it's probably because of your ad. Finally, optimize bad performing keywords with a different bid price and better ads that are more targeted for that keyword.
as ckweb mentioned- split testing is essential. ALWAYS be running a test As far as increasing it - be controversial or out of the norm. i find this gets attention better. Also if you can use numbers and questions that will also boost ctr
Thats makes one of you. Google has TONS of traffic, but the hoops you have to jump through make it almost not worth it.