The company I work for has done several sites using mod_perl and HTML::Template. I'm not sure how to advise you without giving away how we did them, but I'll take a stab.

• Take a leap and go the PerlHandler route. It's not as simple as CGI, but this will alow you to easily separate the site into different functional layers.
• Separate the html completely from the logic. The benefits of this are far to great to list here.
• Don't be afraid to have lots of utility libraries. It will save you lots of code replication (and debugging, etc..).
• objects and inheritance are your friends.

I realize that you're running IIS (you have my sympathy), but you can still make use of the techniques. You may also want to consider a minor porting task on your own if you want to get away from IIS. In one case we were locked in to using MSQL, I took it upon myself to port the database to MySQL on Linux. The benchmarks were convincing enough to move to MySQL (a factor of 10 speed increase). Often just saying there's a better way is just ignored, have benchmarked or demonstratable proof is harder to ignore.

Good luck,

/\/\averick