Not really! Your available configuration options are:
AssignUserID: Takes two parameters, uid and gid (or really, user name
and group name); specifies what uid and gid the vhost will run as
(after parsing the request etc., of course). Note that if you do not
assign a user ID, the default one from Apache will be used.
MaxClientsVHost: A separate MaxClients for the vhost. This can be useful
if, say, half of your vhosts depend on some NFS server (like on
our setup); if the NFS server goes down, you do not want the children
waiting forever on NFS to take the non-NFS-dependent hosts down. This
can thus act as a safety measure, giving "server too busy" on the
NFS-dependent vhosts while keeping the other ones happily running. (Of
course, you could use it to simply keep one site from eating way too
much resources, but there are probably better ways of doing that.)
NiceValue: Lets you nice some requests down, to give them less CPU time.