[Users] oVirt all-in-one install on an already in production server

I have several questions as I have ZERO experience with oVirt and I'm hoping to save myself any headaches before diving in. For the sake of argument, I have a Centos 6.5 box running KVM with several VMs already active. The storage is local, hardware RAID 5 and is set to libvirt default /var/lib/libvirt/images. I would make ISO storage something like /home/iso as that's where I have available space for 20-30 gigs of ISOs. 1. Is this proper in the first place or should I be using freshly installed Virtualization enabled machine? Otherwise: 2. For storage type should I say POSIXFS, ie ext4? 3. Is there any issue with just pointing storage to the libvirt default /var/lib/libvirt/images where my VMs currently live? Thank you for your time.