I agree with some of these ideas and not so much on some of the others, but as long as we are talking about Survival/PVP i think there are aspects that definitely need to change.
Yes there should be a need to play, perhaps a rewards for time spent in game, unlockable kits or a server-side achievement/reward system.
I think there should be a limit on how many personal chests you can lock, this way the player has to put value on what they want to keep safe. If you were in a clan you would have a set amount of safe storage based on how many members you had.
A penalty for pvp related death, not death in general (mobs, fall damage etc.) is what i believe you meant so im going to talk about that. Im partial on the idea of a penalty for death because im shit at pvp, that being said i do think there should be a way to avoid pvp. Now hear me out on this one; When a player is killed a set a certain of times in a set amount of time the option to become passive(not able to damage other players or be damaged by other players) should become available. Being passive would have a time limit or until the next server restart. A cooldown would be in effect if the player disabled passive mode prematurely and a message would show in chat both when the player enabled it and disabled it.
I do like the idea of unique items and events occurring, things like "supply drops" or "legendary mobs" spawning somewhere on the map. A supply drop would have a notification in chat with a drop time and location, this way players would be able to prepare, travel to, and contest the drop zone. The supply drop could have a chance to have a unique item, weapon or armor piece. The legendary mob would spawn in the same manner but upon defeat, it would give the player or clan who kills it an economy reward. The only thing about this is the "random location" would be random in the fact that it could spawn in one of many protected set locations(example: a ruined castle, an abandoned village/town, an empty arena, a wrecked ship, a jungle/desert temple). The only other thing is that mobs that spawn in the world would also have a rare chance to drop unique weapon or item.
XP grinding and enchanting is always an issue on S and most players have a different opinion on what is fair and balanced. I personally would like to see the whole vanilla process disbanded and moved in the direction of economy. Enchants would only be obtained by buying them from the server shop. Also the server shop will buy/sell most items and ores, this way everyone would have access a way to make money and no need to hang on to ten chests of cobblestone. The only thing is that the more you sell any given item the less you get for it/the cheaper it is(just like a real economy). Other ways to get money would be through lottery, killing players and mobs, collecting bounty's, selling heads to the server shop, and winning mini-games.