Moving From CPanel, And Maybe Softlayer

I've finally decided to move from relying on cPanel so much to managing php/mysql/apache on my own, but I have a problem... I host a few people on my server ... Not a lot, but enough to justify some type of cPanel-ish system for their domains. Is there anything free that allows them to manage their emails, FTP accounts, database, etc. while allowing me to manage the server's software? Something that lets me manage the vhosts easily would be great too, but not required.

Since I'm moving off of cPanel, and from CentOS->Debian as a result, I'm going to just buy a new server - however I'm not sure if I want to stick with SoftLayer. They're an amazing company, have great support, great hardware, I've never experienced ANY downtime with them... But I'm paying a bit of a premium - are there any alternatives with the same quality level but a bit cheaper? Even $5-10 cheaper would be fine. I'm looking to switch to a server that's a dualcore, 2gb ram, and at least 1.5tB of bandwidth - I'd rather not pay more than $155/month for that but I'm willing to go up to $200/month (Assuming the hardware and bandwidth scale).
It'd be GREAT if I could get the hardware I listed with a 10mbit unmetered for under $240/month... But, how realistic is that? Softlayer's 10mbit unmetered is $100/month.

I'd also love to be able to build my own server and colo it somewhere, but... So far all the prices I've found don't pay off until you're paying $6-700/month, so that's not looking too good - especially if I have to spend another $4-500 on the server itself.