First beg my pardon I notice a typo in earlier post, should read:
Suggest use -XX:PermSize=192m -XX:MaxPermSize=256m
Regarding - Unless specified maxthreads=200. What I have suggested is to increase minsparethreads since you can realise a default setting of 10 can be not very many threads waiting in pool and forces tomcat to not reach it's potential always removing threads from memory to reduce it's foot print.
Here is the references for tomcat 7, CF10 using a customised 7 not 6:
http://tomcat.apache.org/tomcat-7.0-doc/config/ajp.html
http://tomcat.apache.org/connectors-doc/reference/workers.html
Keep in mind while I have many CF10 production servers they are all IIS and my CF10 apache knowledge is little more that setup configure just to see what it looks like.
To apply a minimum thread setting on IIS tomcat properties file could look similar to EG:
worker.list=cfusion
worker.cfusion.type=ajp13
worker.cfusion.host=localhost
worker.cfusion.port=8012
worker.cfusion.max_reuse_connections=250
worker.cfusion.connection_pool_size = 400
worker.cfusion.connection_pool_minsize= 200
worker.cfusion.connection_pool_timeout = 600
Correspondingly server.xml AJP portion would have this syntax EG:
<Connector port="8012" protocol="AJP/1.3"
redirectPort="8445"
tomcatAuthentication="false"
maxThreads="400"
minSpareThreads="200"
connectionTimeout="600000" />
Something important to mention because I lack enough apache. The tomcat connector and configuration references have some red apache caveats. Applying thread changes that have worked well in an IIS may not suit apache.
You mention your familiar with JVM tuning monitoring. If you are savvy with using JVM tool jconsole (and lesser so jvisualvm) you could use that to monitor graphically what is happening with the tomcat threads. A bit hard to quickly write that up tho if you are interested I did a talk and demo on that and can find the link to recording.
I will post some tomcat native details soon tho I discuss that as well in above mentioned talk.
Regards, Carl.