Autovacuum / full vacuum

hi,

I'm curious as to why autovacuum is not designed to do full vacuum. I 
know that the necessity of doing full vacuums can be reduced by 
increasing the FSM, but in my opinion that is the wrong decision for 
many applications. My application does not continuously 
insert/update/delete tuples at a constant rate. Basically there are long 
periods of relatively few modifications and short burst of high 
activity. Increasing the FSM so that even during these bursts most space 
  would be reused would mean to reduce the available memory for all 
other database tasks.

So my question is: What's the use of an autovacuum daemon if I still 
have to use a cron job to do full vacuums? wouldn't it just be a minor 
job to enhance autovacuum to be able to perform full vacuums, if one 
really wants it to do that - even if some developers think that it's the 
wrong approach?

Mike