For this idea I was imagining the content of TOME/Runescape/Adventure Manager/adom. (limited imagination)

-You start out without picking any class,

     just pick a name, gender, race, and what you look like.

-The choices throughout the game choose who/what you will become.
-Level progression system to were doing actions can give you exp towards that skill, resulting in certain gear/armor being obtainable only by non/combat methods or mixed.
-Zone creatures respawn, and could have a level modifier per number of times the zone has been cleared (something crazy maybe).

     Also the time zone creature respawn could be important too, not just instant respawning from walking in and out of the zone, but something smoother.

-Epic Bosses when triggered can roam, even destroying towns.
-Towns can be invaded by mobs.
-Towns may have a traveling merchant (has rare goods).
-Towns will usually offer different prices for materials, maybe more of a % flux depending on distance away from a certain origin (something like that).
-Towns are your main trade route, investing/selling/crafting your materials you gather along the way. Even being able to purchase land to grow crops, even a house in some towns.

     To make said above interesting, maybe the location of the ore can be relevant to something other than random, also the gear purchased intown and from the traveling merchant will be extremely detrimental to the game, but at the cost of having coins being hard to acquire (no coin drops from certain creatures).

-I liked ADOM's design on character creation where creation on a certain date/time can give you pros/cons, maybe this could have it too, but that might take away from the "be whatever you want" design of this, so these pros/cons could be less gameplay altering, maybe visually, acoustically? (Being born in April could make your person start fat, forever fat custom tile.... just a thought)

Must have skill list:
-Mining
-Smithing
-Herblore
-Summoning
-Fishing
-Farming
-Cooking
-construction (build your own dungeons/houses/traders hut/teleporter/farms)
-Woodcutting
-Fletchery
-Firemaking (Torches, camps at night)

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-Attack
-Strength
-Defence
-Hitpoints - Idk if these should be replaced by cun/str/con/con/dex/mag/will or what the appropriate take on these would be on the TOME engine.
-Ranged
-Magic
-Prayer

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