Is ESXi/vSphere the right product for me?

Hi:

I am new here and don't have experience with VMware, so I respectfully request patience if my questions are simple or inapproriate for this particular sub-forum.

We have an internal test lab that uses the free version of Hyper-V.  The lab isused to test versions of our software product, though the sales and support teams also use it. Due to lack of support for OpenGL 1.5 in Hyper-V, we need to move to another solution.

Our needs for the QA test lab include:

1. Need to run isolated operating systems as VMs on a Dell R710 server with 128 GIG RAM, 2 XEON 5650 processors and 1.7TB disk place.  We may get a second machine someday but for now, there is one server for each office and there is no WAN connection or shared domain/forest between them. 
2. We need to support about 32 VMs on the system above, give or take.  They all can be separate VMs, or some can be a differential disk sort of thing.  At any given point in time, maybe 10-12 are being used interactively.  Though some VMs run only product test automation, most are used by the engineering staff to test the product manually.  We have WinXP -> Win8, 32/64, English/Spanish/etc.
3. **** Important**** The VMs need to support OpenGL 1.5 at a min.  It looks like vSphere can support 2.1.  This product under test now requires OpenGL and will not run without now supporting at least version 1.5.  Hyper-V’s lack of support for OpenGL is the reason we are moving away from it.  Graphics performance is not important, but ability to run the application is critical
4. We need the ability to restore Windows XP --> Windows 8 VMs on a schedule, via some sort of script or API.  We do this now via PowerShell in Hyper-V
5. The VMs need to be part of a domain.  We add them manually to the domain today.
6. Users need to be able to remote desktop to these machines in a separate Window of the desktop, or similar.  The remote machine cannot completely take over their desktop.  They need to switch back and forth on demand.
7. Need to pass a Safenet-Inc (Aladdin) HASP USB licensing dongle- currently accomplished with a DIGI AnywhereUSB device.
8. The VMs need to run as independent machines, meaning we have several VMs today that we restore on schedule, put the daily software build on them, and run automation as a scheduled task, with no user interaction.  We need to still do this.

Nice to Have

1. A way to back-up critical machines.  Two VMs are critical as they run the test.  The rest would be considered test clients and though sad if we lose them, not the end of the world.
2. Dynamic RAM for those operating systems supporting it.  Currently, with Win7/Win8 Enterprise, we can set RAM at 1GB and let it boost up to 32 or 64 GIG if needed.
3. Multi-Core/VM.  We want to run more than 1 core on a VM.  We can run 4 under Server 2008 R2 SP1 Hyper-V
4. VM creation on demand. Citrix has a Lab Manager. Is there something like this for VMware that is not overly expensive?  It seems like I need the Cloud Director Enterprise for 2x$11,000+.  That would have a hard time getting through the budget today.  I am not saying it could not be done, but it might be looked at as overkill.  Can the AutoDeploy from vSphere help?
5. Ability to pass an USB licensing dongle via a user's client machine
6. A nice differential disking system where we have one base OS that we can update later and not have to rebuild 15 vms.
7. Web page where end users can request a VM
8. Ability to use GPU pass through, ideally via the new nVidia virtual GPU coming out.

Current Pain Points:

1. No OpenGL 1.5 support.
2. Adding machines to the domain.  Time spent maintaining machines and getting Windows updates for each VM, then snapshotting again.
3. Time required to bring new machines online.  We have to copy a VM, rename Windows name, add to domain, etc.  Currently, we have a base image which we copy, rename the Windows name, restart, add to domain, restart, get windows updates as there have been more since the original image, etc.
4. Lab is experiencing large slow-downs since Windows 8.  The whole thing is slowing down and we have to restart the host almost weekly. 
5. No VM creation on demand.  Many client users of the test lab are non-IT engineers and they don’t understand VMs.  They will not have access to control them.  If we had a webpage where they would request a VM and have it built with an expiration,, that would be great.  They currently ask the QA team for a VM and the QA team needs to stop their tasks, locate one that is free and tell the engineering staff which one to use.
6. VMs that have not been restored recently grow in space and we need to restore them to dispose of the temporary avhd file.  I think this is thin provisioning in vmware.
7. No user space quota for dynamic disk sizing.  Currently we use dynamic disks in Hyper-V and a few of the managers keep VMs around for a while and the disk size grows.

Thank you