Moving everything to just one server is not that great of an idea if these are critical VMs, because you will have to host redundancy; even if one x3755 could run all the VMs with acceptable performance, you'd want a second one for failover.
Can one of these servers handle it all? Maybe. You need to look at your aggregate CPU usage, memory, storage adapter bandwidth, network adapter bandwidth, disk IOPS etc, and see if it makes sense.
Putting over 30 VMs on local disk is probably not going to perform to your liking, the degree of that depends on how heaviliy these VMs are using the disk. If you already have FC storage set up for this, I would keep them there unless there is another reason why you want to move them.
I am assuming here your seven blades are being managed by vCenter and are not standalone ESXi.