Semi-Dedicated hosting provides the solution. Its a higher level of hosting, which will provide you with a bounty of resources for all your sites' needs:
performance on a Semi-Dedicated plan is better than the same with Shared Hosting
prices for this type of hosting will remain lower than those for a dedicated Virtual Private Server (VPS) solution
the hosting technology and tools (control panel, services and support) provided are as easy to use as the ones for Shared Hosting. No advanced technical skills are required (unlike with VPS plans, which will require administration skills).