If you were happy with your Tikit; my recommendation is to get another Bike Friday.
Maybe even try to find a used Tikit. Bike Friday also has higher weight limit upgrades
on NWT and Pocket Rocket.
Brompton will fold smaller than those models. Also a lot of accessories(+ parts) offered;
both factory and aftermarket. But the ride/handling may not be for you.
You may want to add more info; intended use(commuting, touring, etc.), budget, etc.