ok most of the ideas i have had, seems other people have had aswell and posted, but aww well, im just goign to post mine anyways
Features
Pack-A-Punch Upgrade - i think you should be able to upgrade more then once, but make it another 5000 to up grade example: 1st - 5000, 2nd 10,000 3rd - 15000 and max is like 5 upgrades (this includes more damage, ammo, and more penetration)
Window Upgrades- There should be switches or machines by each window cost 1000 (+1000 each upgrade, max is 4?) which makes it harder for zombies to rip off, making it easier for them high rounds, (1st window zombies pull one, like they do already, 2nd upgrade they pull twice ot knock a plank off and +1 pull each upgrade)
players- i think they should allow more players into the game max 6 or 8 players?
stairs & Floors- They should make a feature where you pay (2000?) for stairs and floors to start moving (escalaters or treadmil effect) so in them high leves with alot of zombies, when they climg up or move towards you, once activated it should slow the zombies back, near a pack a punch machine or something?
Zombie count in the corner of the screen it should tell you how many zombies are left in that round, maybe make an easter egg to activate it?
cars, vans etc...- Depending on the map of course,
make it so you can drive, but make:-
Petrol- you have to pay for petol at certain places
Repairs - make it so you have to repair the car, but zombies can also make it break down and become unusable for rest of the game
Chopper gunner? - for the higher round make a chopper gunner that you can control, (for a certain time + unlimited ammo) costing something like 20,000?
Room customize
Customize doorways and room by building baracades, such as using tables, charis, or even planks off the wall that zombies have ripped off...(zombies can break through the baracades like they do the windoes, but it will obv take more time)
Weapons
customization- create weapons (melee only) like find loose poles, wood, boxes of nails etc... and having to go to a certain places to put the parts together (does it automatically like pack a punch) so when you run out of ammo and knife dont do much, create melee weapons that could be very powerful/funny? examples:
collect shattered glass, turn into a a crazy/fun mirror zombies see funny versions of themselvs and start attacking (like a monkey bomb where it attracts them)
Paintball gun?
collect a tin of paint, tubes etc.. turn into a paint ball gun, once a zombie is shot in the face, it cant see where its goign or what its doing? so it wont go for you
Bowie knife- you start with a normal knife and oyu have to uy the bowie knife like usual, but make the bowie knife upgradable something like:
normal
bowie
sickle
machette (how ever you spell it)
short sword
samurai
samurai x2
Guns:-
ray gun duel weld for 3rd upgrade?
Friendly Gun? (2 ammo per round, but splase damage like thunder gun, but instead of hurting zombies, it turns them on your side, making them attack other zombies..time limit onlly like goes on for 1min and if the zombies havnt died, then they die automatically?)
Last minute gun-
(more like a shockwave effect) one ammo per round, once you have pressed fired, it sends a showave which freezes or paralyzes zombies fora certain amount of time (handy when cornered or trapped)
Cement Gun
Fires Gunge (flamethrower style) that once hits the ground becomes very stick and zombies move 3x slower when they walk over it, at the end of each round the cement sets and then becomes uneffective
Attachments
in the pack-a-punch room, ther should be attachments on the walls tht you can use for the gun, from extended mags - grenade launchers, eveyr single attachment available for a gun should be on the wall
Perks
Perks & Machines
Ammo Machine
To Buy Ammo Costing 5000 for max ammo
scavanger perk
Be Able To Retrieve 1 Bullet For Every 10 kills? or somethign like
Pro
Be able for double the price, once youve brought the perk, be able to upgrade it to pro?
Fun Perks
Examples:
Zombie perk?- a zombie perk which makes zombies think your one of them lasts about 3 mins or so? good for when you run out of ammo and need to do melle or something or even pack a punch or use the box? while this perk is on you also attack like a zombie and cannot use guns or grenades, but you can still pick guns up for when the perk runs out?
electric perks
lasts a minute, electricity runs through your body allowing you to run through zombies electricuting them (insta kill) but to make it more interesting, you can down mates with it?
Sentry gun
Portable Sentry gun costs 4000? lasts 1 round? good for when camping?
Map ideas
Small Maps
Area 51- more high tech guns
Gravyard- for perk machines and stuff you need a shoval and you have to digg certain graves with the perk written on the gravstone? (instead of activating power?)
Cruise ship harpoon gun maybe? bosses that attack bottom of boat, causing water to come in, and if you dont repair it in time, the rooms that get flooded can no longer be used?
Remote islanda plan you was on has crashed on an island, weapons can be purchased off of crates that fell thorughout the island? paack a punch inside the plane?
Medium maps
Mall shopping mall? like dawn of the dead or something?
Zoo Boss? every 5 round a mutated animal breaks out of its cage? different animal each time?
forest/jungledoor-bushes? and pack a punch is in a tree house? there could be huts and stuff from a tribe?
Fun Maps
Strip Clubperks can be purchased from the bar?
Theme Park Ride Amusment Rides? that lead you to differen places? etc... rollercoaster? exits by a pack a punch machine, and ride it again to get back? costs about 500?
Time Travel map? once power is activate, there is a tele port that costs 10,000 and you get teleported to different times, you start off in the year 2011 and it could randomly teleport you to..
medevil times
roman times
cavemen times
or possibly into the future
there is a whole map for each teleportation, it costs 10.000 each time, so when you get bored of one map, just teleport?
Other Ideas
mystery box?
make a 5-10 second rule, if you have a gun from mystery box that you dont want/need your team mate should be able to pick it up if you havnt between 5-10 seconds? who agrees?
Self Revive
Longer bleed out time, and in a certain room there should be a machine where you can revive your self (if no team mates are around or no where near, and the machine costing 5000
Lockers
each player should be able to buy locker for 2000, where they can store a gun eg.. upgraded ray gun or something, so when you die, instead of only having a pistol you can go to the locker and retrieve a gun you put there earlier? lock can hold a max of 4 weapons?
Modding
there should be a modding mode, like unlimited ammo/health/perk etc... mode where you can just have fun with your mate in private or split screen? so if you get really bored and never been to high round but want to know what it feelsl ike, allow people to mod, but score doesnt go up on the leaderboards or anything like that?
Sorry If there are spelling mistakes lol
Hope These Ideas catch your eyes people and i hope you like them and agree some of these things shoulld be introduced into future zombie maps
TREYARCH IF YOU READ THESE PLEASE TAKE SOME IDEAS TO MAKE ZOMBIES MORE FUN/INSTERESTING