The features below I suggest are intended for a time when the game reaches the features of old Arkania:
-Sailing: In RoA 2 and 3 sailing has no serious part but in RoA 1 it has a significant place. After reaching a certain amount of wealth, it should be possible for adventurers to buy their own ship and sail to whichever destination they wish for. The ship would have small harboring cost which is paid to harbormasters and can act as a place to put your loot as well. Another alternative would be to sign to a ship for a voyage as guards or crew (depending on your talents you could even be a helmsman and get paid more. A Driving check perhaps?) With additional sea events such as trading ship encounters where you can hail, trade, or attack(piracy!), pirates boarding your ship, lethal Krakenewt encounters etc etc. the sailing can be a treat. And a delicious Daspota alternative: After getting your ship (or signing to one or helping pirates at some encounter) you could be respected in Daspota, get benefit from their smiths (better rapiers), taverns, brothels a few piracy/smuggling quests perhaps would spice things up. (And yes getting your tattoo and turning your loot in!)
-Towns: Most towns stands there as a place to rest and sell things, before going to your next adventure. Adding fairs/festivals (with tournaments, drinking contests, musical contests, special market stalls etc etc) for certain towns at certain dates would provide an incentive for people to be at somewhere at the right time. And stay for a few days to participate in contests, contracts and shopping. And you do not enter a drinking contest with a Leaf Elf


-Houses: More house events fitting to the lore of the town would be quite nice. Such as a man in Rybon getting angry to the party saying that he could not get away from the likes of -you- despite he lives in a godforsaken town. (Locks the door) Or a house in Varnhome harboring smugglers from Daspota who will be hostile (unless you have your tattoo). Some of them just talks and rumors. That would encourage people to explore cities and towns more.
-Means of Travel: Horses which can be used on horse-friendly roads, coaches which can carry loot would give you a solid reason to invest in Animal Training, Driving and Riding. Of course when climbing through a mountain you'd have to park them somewhere or leave them at an Inn.
-Animal Training: Especially druids could do with a helpful familiar which cannot be controlled by party directly (except Druid could order to stand, flee or attack). The orders depending on Animal Training skill, may fail. At your free time in Inns or at Camps you can use that talent to train animal for fighting, intelligence or health. Train horses to be sturdy against weather or to be faster etc.
-New Dungeons: The more, the merrier. No need to explain it

-Taverns: Some taverns could refuse to serve you depending on your clothes, wealth or your fame/infamy. If you get caught cheating you'd get beaten, thrown out or lose a part of your coins. They might not let you gamble there again or innkeeper can raise his prices for you. At worst case they might even bar the tavern entrance for a few months. In contrast Tailoring shops which does custom clothes for your character which makes them seem more presentable could be implemented. Who will dare to refuse a lavish looking gentleman to their fine establishment? (And what kind of thief will let such a rich looking gentleman go unscatched at an alley?

-Adventuring Parties: Other adventuring parties, good/neutral/evil which can cause conflict, give rumors or trade with you simply. Nothing is more lethal then a roving band of lunatic dwarves who deems you evil and are after your coin purse in order to give them away to local orphanage!
That is all I can think of for now. But I am positive these features would enhance the spirit of Arkania.