Managing Saas Environments

We have customer who has only 2 SaaS Environments provisioned. They are having challenges in managing their environments effectively considering the following activities.

1. Testing (patch, regression and other testing)
2. End-user Training
3. Troubleshooting PROD issues (P2T needs at least 4 weeks)
4. Enhancement / Improvement / Addition (like setting-up new subsidiary)
5. Development / Integration 

Any best practices that you can share which will help them to manage their environments effectively please share,

Thanks

Govind