Need Advice for Best Package w/ These Requirements

All,

My site currently runs OpenPublish in a shared hosting environment - when I decided to go with OpenPublish (OP), the Drupal community recommended PinchHost as a viable option for running OP in a shared environment.

Things are ok at the moment, but I've got a couple of projects in the pipeline. Primarily, I want to combine Managing News with Tattler to create a data mining application that can be used to provide research and source material for the OP site. Then I want to use OpenAtrium to create a collaborative space where research projects can be worked on with multiple users. The various installs would share user tables so that a login in one would log the user in to the other spaces. I would offset hosting costs through ad revenue on the OP side plus membership for any user who wanted to use the data mining to produce material that would not be published on my site.

In the mean time, I'm of limited means and am comparison shopping different hosting solutions. OP already ties up my current package if I do too much.

OP requires: 2GB RAM

Tattler requires: 2GB RAM and cron must run every 5-10 minutes.

OpenAtrium requires: 64MB RAM

ManagingNews requires: 32 MB RAM

So I'm imagining a solution that would take 4/5GB of RAM since I want to have some leeway if there are traffic spikes. Looking at the packages, it would seem I need a Linode4096, but I don't need that much storage or bandwidth. I could do with the storage in 512 or 768 at this point. Is there a way to get a 512 or 768 and add on the extra RAM? (Or have I miscalculated my needs?)