Druids are the entry level shifters, which have already been regulated - see: plantshape - and, if people get too funky playing lapcats, will probably get regulated once more.
Plantshape, Animal Shape + Totem, Elemental Shape, Shapechange to include: Red Dragon, Fire Giant, Balor, Death Slaad, or Iron Golem.
While not available for druids, but wandable/scrollable, you have Polymorph Self to include: Giant Spider, Troll, Umber Hulk, Pixie and Zombie.
And beyond that, there is also baleful polymorph for a few other options.
Beyond the changing of Dragonshape to Plantshape, I don't really see the regulation here. And even then, Shapechange still lets you access to a dragon form.
There's no "problematic portion"; the whole concept of the class is about being able to take any shape, in its essence and in line of the expectations of Arelith, the entire concept of a shifter is problematic.
If taking any shape is the portion that's problematic, then, as I already mentioned, why not decouple that? Why not have shifter available as an existing class available for everyone, with a very limited set of shapes, and an application would open it up to more?
If, for example, non-application shifter only permitted the exact same shapechanges that a druid could do, but with the new mechanical benefits of the rework, would there really be any issue with that? And an application would grant them access to whatever the remaining shapes are, giving them the same combat ability, but with extra tools for RP.
It may, however, be on the table to change the award cost.
Unless you mean to say that it will be costing an award in the future, it already doesn't cost an award.