Their are really only a few ways to view this -

1) Tables can be used to build a validated, nice looking site, cross browser compatible, with exceptional SE ranking. This is a fact . . . for now.

2) The use of tables seems to becoming less desireable by the W3C and the SE's - especially in terms of accessibility. You can try to ignore trends but things do move on.

3) CSS, at present, is the way to go if you are a forward thinker. We are migrating this direction. Sure it has some challenges but we have been very pleased with the progress and performance

Change is not always fun and always involves more effort to implement. The end result is better 99% of the time. If you want to make it easier try to utilize a site with more white space and less graphics that touch/overlap. Avoiding these critical alignment situations will alleviate a lot of hassles.

You could redesign your site with tables and have it ranked well and then find yourself down the road in another two years wondering why you didn't use CSS. My suggestion is to take the time to learn it, build it out and upload it. Your existing site sounds like it is okay for now. Take time, enjoy learning and get ready for the next phase in web design.