Our company is using eclipse since several years now (we are using WTP since release 0.7)
I am currently evaluating eclipse 3.6.2 with WTP 3.2.3 which s
We have the same problem with WTP 3.2.3 here, too. We use it in our product for several years, too but the acceptance of our developers and customers in this tool is decreasing every year because in every newer release it is slower and slower.
I would like to use it if I could disable all "advanced" features but as you mentioned you cannot disable the indexers at all. Also you cannot stop the validator of JSP files if it is already running (you can test this if you have that many files as you have and we also have around 1000 JSP files and many tag files in our project).
I also can prove that increasing the memory does not help. It only prevents crashes of the whole eclipse but it does not reduce the UI blocking internal operations of WTP.
In the newest version 3.2.3 I got many hangs when I start Tomcat from within the servers view. The UI just hangs about 1 minute. It's not only me who has the hangs, it's all my colleagues who work on Windows have the same problem. On Linux I do not know about this problem.
Also there are problems in WTP when you have no access to the internet. It seems there are request to some registries to download schemas or such things and if you do not have a connection then it just hangs and waits for the time out.