pm me if you want to meet up at LAC.
Some quick answers:
.co.uk would be better to convert UK traffic and also rank higher for Uk search engines.
Increasing your conversions is not an easy answer however there are many articles and books coming out on the subject and it’s best to do the research yourself or hire one of these call to action experts. Check out Multivariate Testing Website Optimizer. Just ask yourself when you are on a site if you are lost or you know what you want to do such as which links to click on or maybe there is a good call to action to join their newsletter.
John