These are in no specific order just as I think of them while I type.
1) All weapons and cars from online sold offline on websites. Actually ALL cars and weapons in the game available to purchase in single player.
2) Non-claravoyaint cops. I'm tired of cops being tipped off by animals, or going to where I was and automatically know I am hiding somewhere else. Let them search a zone the higher the stars the bigger the zone. Extend the amount of time they search but let them look around, not just automatically know where I am. Unless someone sees me (a citizen) go that way and reports it. Have roadblocks on each road out of the zone at higher star levels and no matter what if you have no gun let them arrest you at all but the highest cop level. Level One: Arrest, Search Area: 100ft circle; Level Two: Mase and Arrest, 500ft search zone circle; Level Three: Tase and Arrest, 2000ft search zone; Level Four: Shoot to Kill if armed, 1 mile search zone; Level Five: Straight up you gotta Die!, 3 mile search zone. Have more intensive searching in the zone and very light outside the zone. Stop having the cops randomly insta-spawn in front of pay and sprays, Stop having them insta-spawn directly in front of you constantly at higher levels. If you barricade in a building and keep killing all cops who come in have them hold the perimeter until you come out and then smoke you, or throw in gas and knock you out. Also have all vehicles have the same speed and stats no matter who drives them. I find it funny if I drive the fastest car in the game but not only can the cop car keep up but it can put on a burst of speed to ram me! Utter crap!
3) Be able to drop weapons, or if you have to keep all the weapons on you, have it so you can choose favorites that always are at the top of each type of weapons list.
4) When I steal a car and change it's plates and repaint it it should be mine. Don't let cars we park in garages disappear if they have been chop-shopped. This whole list is because I parked a Dukes in Trevor's trailer's garage and went to drive it and it was magically gone after having been in there for over two weeks real time and multiple uses. All of a sudden... presto... gone!
5) Have suppressed weapons actually be suppressed or reduce the distance a scream from someone dying can be heard. There is no real point to suppressors in V because if you shoot someone everyone else seems to hear them die and panics and runs.
6) Even at the highest cop levels still have civilians around until roadblocks are set up. And if you get past the roadblocks have them return. It is bull that when I start killing cops everyone is just... poof... gone. Not only that all the parked cars seem to disappear.
7) Put a speedometer on the HUD.
8) Make the cars use gas and make gas stations useable.
9) Have more than two car washes on the map and have them spread out.
10) If you are going to have multiple store chains, have them sell different stuff. Binco and Discount stores both sell the exact same stuff. Pointless.
11) Have different looking people running the different stores instead of the same chick no matter which Binco store you go into.
12) Let us eat at restaurants again and food vendors as well as pop and chip/candy machines for health. Let us eat and drink even if our health is full. Let us buy drinks in variety stores not just munchies.
13) Allow us more idle time stuff to do. Sometimes I would like to just sit on a park bench and watch the world go by. Also the roller coaster and ferris wheel were a joke. Having more than one place to play darts would have been nice too. Plus why not add basketball, table tennis, or add video games back in again.
14) Increase the speed cars can go. I drove the Adder with all three guys but the top speed I could do was something like 130; unless I used Franklin's skill. A supercar should go over 200mph.
15) Have AI cars randomized by the parts they have on them, not all just stock. I liked that you added some special cars sitting near the one Pay n' Spray in downtown LS and some sat in various spots around the city but they should also be driving around. And not just the high end cars. Joe average AI should be able to put different rims on his car.
16) Have more interiors. Let us rob houses again, Let us hang out in more bars than just the strip club. Let us hang out in restaurants and coffee shops.
17) Give us bigger garages to store vehicles in. I was hyped about buying the garages for my guys until I found out they just held 4 cars. The hint boxes gave the impression you could store infinite amounts of vehicles in them.
18) Have all weapons, gear and cars available to buy from the start. If I want to save my money to buy an Assault Rifle instead of just piddling around with a low damage SMG I should be able too.
19) Add more jobs to make money. Let us get jobs instead of having to steal a taxi. Let us go in and get a car assigned. Add varying jobs like bouncer where you have to check IDs and kick people out. Or a delivery driver, for packages or vehicles. Or Repo guy or Bounty Hunter, or Tow Truck Driver with more than six missions that when you do them they are done. Let us make money at them.
20) Either have stop signs or stop lights. Make up your minds. Plus have one side go at the same time and then the other (ie north/south then east/west). I mean all cars and pedestrians. Have the lights stay green a little longer, but let me not have to wait five minutes at a light to get through. Synchronize the lights so when one is green in one direction all lights are green. Have more lights green when I come up to them. I like to drive like I am in real life but it pisses me off when EVERY light I come to in my route is red for me. And when I stop no one is moving at all in either direction.
21) All convertible roofs should work. Cars with automatic spoilers should work as well. Also if I turn my lights on during the day leave them on instead of automatically going off after 30 seconds.
22) Slow the global clock down a bit. I get ticked when I take a walk and go six blocks and it goes from 1pm to 5pm. I know that time has to run faster but it doesn't need to be that fast! It takes me out of immersion when I walk around the block and it is midnight by the time I get home.
23) Let us rent motel and hotel rooms to sleep in, instead of always having to go home to sleep.
24) Have a choice for vehicle music but NO background music. I love listening to the radio but I hate just random background music when I am walking around. I would like to hear the sounds of the city, not BG music. And it is a bother to turn off music everytime I get out of a car and then turn it back on when I get back into one.
25) Give us more things to do inside our houses. Not only drink a beer but eat a sandwich or something. Not just watch tv but play video games. Or turn on a stereo and listen to music.
26) Give us things that we can keep doing after the main mission is completed so we can keep feeling there is someting to do with the game besides just killing sprees.
That's all for now if I think of more I will add them.