OK, I understand if you want to wait for full release of 5.5, before you install it. Anyway, it's coming very soon
In 5.0, the ways to decrease the data you are gathering are
1. disable some collection rules
2. increase collection interval globally
3. disable some metric classes
For (1), you could disable some rules - I would suggest perhaps VMHost-Disk reads and writes (since we anyway collect kbRead and kbWritten). Perhaps also disable VMHost-Disk deviceWriteLatency and deviceReadLatency (since we anyway collect totalWriteLatency and totalReadLatency).
Of course you lose some visibility of data doing that - but you still are collecting the most important counters. And all Monitors will still work anyway.
For (2), you already saw the Collection Interval drop-down in Management Center UI. You could increase that - but note, that in 5.0 this will affect ALL metrics. It affects performance collection (for graphs) and also Monitors. With this method you still get all counters, just delivered less often.
For (3) you can turn off a data class completely. For example, you could turn of VMHost-Disk class. Use the nworks Management Center UI to do this, just uncheck the class name. However you would then have no metrics at all for Host Disks....I would not recommend that, these are important metrics. If you really want to reduce collected data, you might also want to look at the VM-level metrics. Since there are so many more VMs than Hosts, they generate more data....perhaps disable VM-DISK and VM-NET classes. This can be OK, especially if you have Ops Mgr agents inside most VMs - -they will already be collecting Disk and Network I/O, so there might be duplication there.
Hope that helps - and watch out for the notice from Veeam that 5.5 MP has released!
It has all the new features you need to control this performance collection.