Things I would change/add/remove in Pvz 3
Levels
probably said multiple times and by multiple people but make the levels longer because you barely have time to set up a proper defence and it makes tier three plants (except sun tower) worthless to obtain
try to add levels with special objectives/gimmicks to make levels feel more unique and less stale you could add gimmicks from other pvz games like don't let the zombies trample the flowers and even make new ones such as merge x plants beat a level without tier 3 plants etc.
add more effects like the sod tiles,rain tiles and the nacho cheese blast and make some of them benefit plants some benefit zombies and some can effect both
some examples
lightning zaps a tile destroys all non lightning plants in that lane zombies and non lightning plants in a 3x3 area that are here take damage over time (only umbrella leaf + zaptail merges can both prevent it and benefit from it)
wind: depending which direction can benefit the plants or the zombies
Locations
there are not nearly enough locations for there being 200 levels
ideas
Location: Spooky cemetery: introduces gravestones + light and heavy fog (light fog similar to pvz 1 hard to see zombies but plants can still attack zombies. Heavy fog develops overtime if fog is not removed and most plants can't attack zombies in it heavy fog)
Zombies: Grave repair zombie: repairs and fortifies gravestones, coffin zombie: has heavy armor when destroyed either a zombie or imps come out of the coffin: skeleton zombie when destroyed falls into a pile of bones and respawns in not destroyed in time.Gravedigger zombie: summons graves and summons zombies from graves when below half health.Dark wizard zombie: all zombies in a 5x5 area around him take 20% less damage and turn into gravestones when defeated: trick or treater zombie: gives candy to boost either zombies health or damage.
Plants (Tier 1) grave buster: ghost pepper: Jack o Lantern. Witch hazel candy corn
Location: Z tech laboratory: introduces tiles with special effects such as speed boost health boosts and more
Zombies: genetic experiment zombie: gets stronger when affected by both positive and negative effects. Alchemist: gives zombies random buffs. Chemist gives random plants debuffs. Gadget scientist: can create special tiles to benefit zombie. teleportation zombie: teleport another zombie in a 5x5 area around him two tiles forward
Plants(Tier 1) Em peach Tile turnip electric currant hurrikale dandelion
Plant leveling
I personally do not like plant levelling in Pvz 3 because it makes the game more grindy and makes fusion plants less impactful and an idea to replace this (which is in one of my posts in more detail) is to level up your block every 20 levels or so and it still gives you something to work towards can possible give customization a purpose and can give effects like more mowers more seed slots or even unique effects like the first zombie to spawn is chilled etc instead of just health damage and ability cool-downs
also the games way to balance plant leveling by giving zombies more health and damage is not a good way to go because eventually the game gets locked because the zombies the zombies just have too much health.
and personally I don't see why you don't add zombies that can give other zombies those buffs instead
Zen Garden
first of all REMOVE THE HEART SYSTEM While I understand having to wait for them to grow I don't think we should be limited to how many we can place. I personally would not mind if we had to obtain these zen garden sprouts by killing zombies to balance it out so people just can't place a lot of sprouts very early on.
also add more pots so we are able to plant more seeds
while I don't mind playing mini games for resources I am not a fan of the current "odd jobs" mini-games just bring back pvz mini games like wall nut bowling,whack a zombie etc.
Avatar
while this is one I care about the least at least give the characters some expressions because them standing there doing nothing is weird or have an option to have them not there at all
Communities
while the communities itself are good so far in the beta some things to add are
-Chat,more people per community, community vs community etc
Other game modes
some game modes to add as you can unlock while playing the game
mini games such as wall nut bowling whack a zombie boss battles etc
endless mode
puzzle mode
level editor/creator
rewards for completing these (except endless and level editor) could be seeds after the first and second win and coins for all tries after that
Online mode
this could be just me but I love vs mode in pvz 1 and while I have no idea why it is not in pvz 2 I think It would be a fun idea to add to pvz 3