I don't think a stand-alone senior tour would go. As Jakeev says, it would be hard to round up 24-32 players for each of, say, a dozen events or so. Plus, half or more of the events would wind up in the US, and I'm not sure we'd support that many. And you need a greater variety of players.
I'd like to see a senior tour established within the confines of the main WTA tour. It shouldn't be too hard to find 8, 10, or 12 tournament sites which currently host Tier IV's or V's (or the odd III) that could handle an extra 8-16 singles tourney, with half that in doubles. There are a lot of players who retired in the last several years who could still play some good, entertaining tennis.
If they tie these in with the senior events at the slams, it could work. Start small, and make sure everything is well coordinated. Perhaps they could poll the various regions that host the lower-tier events and see where there might be interest. There are bound to be some places that would enjoy seeing the likes of Basuki, Wiesner, Tauziat, Hy-Boulais, Novotna, Date, etc., playing each other in real matches with money and ranking points on the line. A lot of former players are already in or near these tournament cities, either broadcasting or coaching. Plus, these senior matches would make good filler for the evening session, after the main tournament's feature singles match. Promote it with photo ops and autograph sessions, and it could be somewhat successful.
And here's an idea: each senior event would have a contest, where some lucky local woman gets to play doubles with a legend in the doubles portion of the senior tournament. A real, honest-to-goodness match. This would, of course, require one player to make a sacrifice at each tournament, knowing she's giving up any shot of winning the doubles. This duty could be rotated among the top doubles players on the senior tour, so it balances out.