There is one correction I should make. On line 520 replace:
my $pool_name=$ranked_pools[$i]->{name};
with
my $pool_name=$pool->{name};
. It is some threading race issue I was working on which crashes the pool once a day or so.
When making this tweak, I noticed some nearby code specific to Slush that seems to handle multiple workers. Did you find it necessary/beneficial to have multiple workers configured for each pool? Just for Slush? Is there any special syntax needed for specifying additional workers in the accounts.conf file, or do I just have multiple line-entries for Slush?
Multiclone is up to about 3-4 GHash/sec now, and seems to be handling things beautifully. Total CPU load average on the server is under 7%. Looks like there's room in the pool for everyone; jump on in!

Did a quick reboot of the pool to enable to tweak, expecting to see a disconnected/reconnecting message, but the process was so quick my miner didn't even seem to notice. Looked like everyone who had been connected successfully reconnected after the restart. Cool.