I'm not trying to say "Yes" or "No" here. Just add some thoughts. I think the current VS system seems to treat people quite fairly and reasonably.
The only thing I'd really like for VS at Au level would be either access to a special award seat inventory or a waitlist for upgrades, rather than the current fun and games.
Well, I guess UA have an extra higher tier, earnable by qualifying miles (UA using a qualifying miles system, rather than tier points), as they have "1K" membership, which gives a few extra perks over UA's "Gold" equivalent (Premier Exec).
1K benefits are things like a couple of complimentary systemwide upgrade vouchers per year, better upgrade and bumping privs, access to a special award inventory (i.e. they can book reward tickets/upgrades when they appear to have all sold through), seperate check-in, dedicated 1K service desk (usually very experienced reservations agents), etc.
UA also have a bonus such that if you fly more than 1 Million miles on UA metal, you become Premier Exec for life, I think as long as you earn or redeem miles at least once per year (i.e. general terms to remain a Mileage Plus member).
On top of this, there's the mysterious "United Global Services" level, which is their equivalent of BA Premier - super high revenue frequent pax, key people in large companies who have corporate travel arrangements with UA, etc.
So, GBTOPs or V50s, call them what you will, seem to be somewhere in between 1K and UGS if you look at UA's scheme.
UA have also introduced an "interim" awards system, to keep people flying and earning once they have qualified a level. I've just passed 35000 EQMs on UA this year, so I've requalified at least as Silver at 25000 EQMs, and for passing 35000 EQMs, I get a choice of things like restaurant vouchers, or carry forward a small number (e.g. 2.5k) of EQMs into your next qualifying year, to give it a boost start.
Once I go past 50k EQMs, I've requalified Premier Exec/Gold, and then if I get to something like 60-70k EQMs, I get another incentive, like carrying forward more miles, or rental car upgrades, that sort of thing.
Seems like a nice idea to keep "marginal" people flying beyond just what they need to make or retain a status level.
I guess that the V50/GBTOP would lose some of it's status if it got too big, so maybe something like a "Gold Plus" at 70/80TPs would be a good way to go. Include something like extra Clubhouse Guests when flying VS, and/or ability for the member to use the VS Clubhouses regardless of departing airline as long as you are flying from the same terminal.
Add in some special Gold Plus events, four complimentary one-cabin upgrade vouchers (and/or complimentary car transfers), and some special route to VS Management for dealing with issues - i.e. Gold Plus members have a direct contact for the PAs to the Directors?
Too much? Too little?
Mike