Thank you for all your kind responses. Here are the answers to your queries:
1) Currently I am using VPSLatch (apparantly owned by DimeHost). I have a 2 GB VPS there for $45 per month (got in a sale).
2) Yes, the Wordpress sites uses MANY inefficient plugins. All kinds of plugins. Mostly slideshows, photo galleries, etc. Most of the websites are for clients and they need to have those plugins :-(
3) All-in-one-SEO is used on a few sites too but I am shifting every such site to Yaost plugin.
4) Currently there are ONLY 50 websites on that 2 GB VPS.
5) I need at least 4 IPs because some clients require separate IPs. I believe with VPS and Dedicated servers, 4 - 8 IPs come along. So, I will get it in $100-$125.
6) I need root access because sometimes I need to install Apache modules or fix other things. I am programming for 10 years, so I get comfortable with root access.
1) If I go with a dedicated server, which server and where should I go? IS HIVELOCITY GOOD ? They have nice servers in $120 range.
2) If I take unlimited SITE5.COM plan, won't they kick me out ? This plan:
Please advise and thanks everyone for your responses.