I would dearly appreciate, if for a change, FE broke the old model that all games I can think about follow... i.e the best strategy for enchantment is first and foremost to pile them up on your most powerful units, and if you have really spare juice, a few basics units get some.
i.e Master of Magic, Age of Wonders, Warlord, Warlock and a few others.
Now, players are not the culprits here, it is just that when you have strong units, adding up more strength to transform them into juggernaut IS the best strategy.
So, in the same way that numerous design possibilities now exist and are well known to combat the infamous 'infinite city spawn' effect, aka ICS, it would be cool to find ways of combating this trend... Why, because it would be more fun in the end, first to not have the need of only an handful of unit to conquer a kingdom, second because it would lead to more diverse approaches and varied strategies.
A proposal would be to up the maintenance cost of enchantments, if on same unit, exponentially. i.e the more you have on a same unit, the costlier it is, for each new one.
There are others possibilities, and I'm sure Derek can find some, if he finds my problem, his problem too At least, I have vented my concern, if nothing else!