fortifications and defences

i have an idea for new fortifications for provinces. i will be proposing improvments for the already existing fortifications as with more new types of defences. first, the improvements on the fortification are that they would provide a defences boost too defending troops. the way it will do it is by subtracting an amount of percentage of damage taken by the troops defending there. each level will include an increase of this percentage. level 1 would start at 20%, for exaple: defending troops take 20% less damage from attacking enemies. each level would increase this percent by 10%, resulting in the max at level 5 being 60% less damage. i reall would like this feature think it makes alot of sense. second, i would like to see coastal naval cannons, this is a fortification that will add coastal defences to the province that has the range of a battleship, the cannons where often the same as battleship cannons so this would make sense. these guns can only attack ships and the damage increases with each level, the damage each level would be the same as a crusier.once the troops have finally loaded on the province the cannons would stop firing. this would basically act as a permanent artillery in the province for the coast and the sea. third is a normal artillery forifacation for provinces, it would have the same damage as normal artillery with each level but the range will cover the entire province with a little bit larger range to cover just abit more than the province so you could defend against troops getting close to the border(not to far into other provinces though).the fourth and last would be air defences in the province. when planes attack they would be hit just like normal aa. it would have the same damage as normal aa. the stats could change acordingly to the devs likes and everyone please give me your opinion good or bad(please dont be that mean) thanks