I never thought it would 'make the meta go away' just make it more interesting

Its one or the other. If there is meta it will be the same level of interesting. Once people know which 6 are best it would be the exact same thing as it is now.

And I don't think people who solo/duo would stop, just change up their strategy.

Several of those strategy's revolve around finding/evolving/leveling/TMing 1 perfect counter team. Your change would simply eliminate those that did that and add nothing really fresh to the game. Except for forcing people to try and find those top 6 and then never change off them.

but I also think its worth it.

Personally I don't and I don't even have a full team of anything yet either. Your proposal does not add anything new or interesting. All it does is change the meta and screw people that worked in the current system.

If you are bored with the system then change how you play. Dont make other change to suit your interest. If people want to play with more types they are totally free to do so now.