while playing the game, I have thought that it might be great if we could use stored troops for attacking.
Let me elaborate.
That way players could make up a good defense for the castle (with units that are best for defense) and leave weaker units in the inventory, thus suffering less damage from intruders. When attacking, those weaker units, however, would come in handy as cannon fodder. So, that way I wouldn't have to have them for castle defense but I could still use them for assaults... Do you see what I mean?
It would be great if we could place towers in the inventory to get space for mobile units (just to try different defense setups, because now we can just sell a tower to get additional space)... And, if we sell, it means we have to rebuild...
Also, towers should definitely have the higher shooting range in the game. Otherwise they're kind of useless against balistas who can take them out, not taking a single point of damage...
One more thing about towers: you count them as one unit (takes up one living space). However, when we attack other players, towers count as buildings (i.e. we destroy a tower and get one enemy building destroyed, not one enemy unit destroyed). It might confuse players. Maybe a more consistent approach is in order?