Custom Tags with Selectable Values

My organization would like the ability within tag group editor to be able to create and set default tag names and define a "selectable" set of tag values via a drop-down. We have large number of single-session personal AVDs used by various numbers of partner organizations. The goal is to simplify VM operations by creating a more generic pool structure, but utilize tagging for uniquely identifying assets and eventually, potentially charge backs to the business. If we had to create a selectable tag group with all values prefilled, we would have hundreds of different tag groups (for every combination of values). We're trying to do this tagging with the open text boxes, but typos, misspellings and just general carelessness are really skewing our reporting. This would be a huge help! Thanks!