The best replacement for vcenter is vsphere.

The best alternatives to vcenter are rated as following:
★★★★★  vsphere
★★★★  esx
★★  openstack
★★  scvmm
★★  vsphere client
★★  vcsa
★★  vcops
★  xencenter
★  system center
★  esxi
  vmotion

Your alternative for vcenter is not listed? Suggest!
Speaking about vcenter, one probably shouldn't forget about sql express.

Other search terms related to vcenter and their ratings are:
★★★★★ sql express
★★★★★ esxi
★★★★★ free esxi
★ shared storage
★ veeam
vmotion
You have in mind a companion for vcenter and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of vcenter in all years. Click on graph for more.
vcenter
vsphere
esx