1. start with a world where travelling (adventuring) during part of the year is much more onerous and rarely done. Such as during the harsh midwinter. This is initially a time for the characters to spend in downtime, resting and healing up.
2.Give them reasons to take time away from adventuring. I have several that I use. recovering from Lingering injuries that take a few weeks to recover from (not losing an eye or hands cut off just things they can adventure with but don’t want to like injured leg: 10 to speed, frail: -2hp per level, scarred: disadvantage on Dex ability checks etc) as a stick and Peak condition benefits that they can gain by spending weeks on downtime (Agile: force an enemy to reroll an attack against you, Hardy: automatic 20 on a death save) as a carrot. I also require level training but only for odd levels and you can do the training at any time (so now they are 8th level about half have completed their training to get to 9th) giving the players control means you can make the training take a while and it probably won’t interrupt the adventure flow. For mine 9th level takes 20 days. They spread that out when they can.
3. give less xp than normal AND wandering monsters or non story monsters are only worth 1/2 that. Those things should be avoided.
4. make healing potions expensive and encourage them to use them. I started with healing costing 100gp and when you drunk from it you rolled a d4. Only on a 1 was the potion used up. (I do this for almost all potions) The effect of this is that they use more freely allowing them to keep adventuring and they burn through their cash. In my campaign due to reasons the price of healing potions recently doubled. More than once an adventurer has complained that the paltry treasure he got was less than he lost on healing potions.
5. Have some adventures be treasure finding ones but others not. The party chased off some gnolls who were harassing travellers. They get a few coins maybe a potion and a valuable (non magic) sword, they spend a few hundred gold worth of potions and they get the gratitude of the town. But they also hear about the Chimera that has lived in the caves for decades. The encounters on the way to that encounter again suck for treasure but if the Kill the Chimera they make out like bandits. (My campaign has 8 players and at 3rd level they found out where a black dragon laired, at 6th (about 2 real and game years later) they geared up and slew that dragon in its lair. They couldn’t get horses there but had 2 tensers discs and a bag of holding worth of mostly silver value loot items. Unfortunately the town they were returning to was under seige by orcs when they got near and they lost most of their loot to the orc army. They were grumpy but they did help lift the seige (the Orcs were happy with their wealth and left) so are now heroes of the town. They have since been looking for another big treasure haul and have now (about another year later) just recently discovered a path to a lost “city of treasures” while they are sceptical they are keen to try and make some cash.
6. I also don’t allow hp recovery over long rests without spending hit dice.
7. Make downtime excellent as possible. In my game the main city they spend time in had only a low level priest of Pelor so the PC has become the head of the temple in the region. She was 7th when that happened (now 8th) and she has a couple of priests in the city church who deal with things when she adventures but also a small network of churches in neighbouring towns which she visits and one town without a temple which she is trying to establish one. There are also wealthy lay worshippers who help her out in non adventuring ways.
8. Have at least one rival adventuring group, secretive about what they do, but don’t make them total dicks and Also members from retired adventuring groups scattered around. If the PC’s leave some titbit of adventure too long have a rival go do it. If the party is about to be wiped out and you want to save them have the rival group show up - and expect a reward.
9. Have them rescue a good creature that shows them there is more to the world. In my game they helped out a Sprite knight and have now learned about the battle between the Fellgloom coven of Hags and The Orchid Court of Sprites. They have been given help by the court and have wiped out one of the Fellgloom covens subject covens The Illwarden’s. This gives them enemies and friends. I admit that I tend to overdo the plot threads in my games.
10. very importantly very now and them ask your players which stuff they want to explore and what their characters want to do. I find about half are happy to just go along for the ride, the other half will want to explore your world.
11. try and aloow some downtime stuff to be done out of session. About half my players have little interest in the downtime side which is fine they enjoy a game of monster hunting, adventure stories and treasure. Dont worry about this. The other half have heaps of stuff they want to explore.
the rule change I am most happily surprised with is either 2 or 4 above (3 is a given as I wanted the game to last several years after running multiple fast levelling campaigns) probably 4. This easy access to healing at a price that seems innocuous both encourages PCs to self heal and spend their cash. This also solves the problem of what do they do with their gold. Because there is a good chance the potion is still there after they use it they are encouraged to give it a go. The players get joy out of a potion that they get to use 6 times before it fails and at one stage they confronted a vendor because they kept rolling 1’s on the first sip. If the potion is a (d6) potion it means on a 1 it gets reduced to (d4). FWIW I’m told a d4 potion should get 4 uses, a d6 10 uses etc.
much longer than I intended - oops
