Nick - it's tough to try to pick up a game like this when it's been in the App Store for > 2 years. Unfortunately, with the changes PSG has made to the higher Tier matchmaking (mainly, two players cannot match in T7 until both have played 10 matches in between), it has pushed the top tier players down to low stakes to get those "in between" games in so they can head back to T7. To add to it, the players that don't want to go through the hassle of playing 10 matches in between have just stopped playing top tiers altogether, and moved down to the lower tiers to complete Perfect Pass (this is the majority of players).
I agree that the matchmaking system needs a revamp to take player level into consideration. The potential issue with this change (from the top tier player side) is that it will only add to matchmaking wait times in the higher tiers - something that will (and already has) cause the most active players to lose interest and go elsewhere with their time/money.
It really is a double-edged sword on the dev side - a change needs to happen, but no matter the change, they will be pissing off one player group or another.
I think a good compromise would be to have a "ranked" match lobby and an "open" match lobby; it could possibly just be a radio button added to the settings menu as well - where a player can check the "Ranked Matchmaking" box to be matched based on player level (at the sacrifice of longer matchmaking wait times), or can uncheck the box to be matched with the first available player (that also has the box unchecked) that enters the matchmaking lobby (at the sacrifice of potentially matching with a more experienced player).
The above suggestion gives the player the choice based on their preference, greatly reducing wait times for the players that aren't concerned who they are matching against, as well as protecting newer players from getting demolished in the lower tiers.
My $0.02 - I hope they can implement a change sooner rather than later.