1. the monsters don't change based on location on the world map directly, but they do get stronger the farther you get from the road. Monsters are pretty easy if you stay on the roads.
2. Castles, forts, and outposts, don't have bounties quite like you are thinking. You go into them and go into the office portion of them. There you can look at stuff like a bulletin board (I've only been to forts and they tend to have 3 dungeons listed separated by the "more" command.) that tells the location of a dungeon and how much gold you will get for clearing it out. For example, it will say "You will receive 4000 gold for clearing out a dungeon 16 miles to the north and 3 miles to the west) which gives you directions to the dungeon in question. complete the dungeon and go back to the fort, castle, or outpost, which will specifically have those words in their name, just as you can tell a lot about a town depending on whether it is a city, town, village, or hamlet, which tells you the general quality of items you can find in the shops and how many establishments there'll be in the city, with hamlets usually having 2-3, villages have 6 or so, towns have 10 or so and cities usually have at least one of every type of shop, several temples, often a bardic college which allows you to customize the narration voice, (I'm working with the high-elven female accent.)
3. If you cleared out a monster-infested castle, you will later, with money, be able to claim it as your own, a lot of smart monsters like orcs, goblins, and stuff like that actually carry deeds to different castle structures that dramatically reduce the cost of improving your castles. (note I just know this from listening around taverns, reading the help stuff, and paying attention to the news each time I get on.) Was particularly tickled when I found plans for the Dressing Room on some orcs.
4. The game taking a very long time to make progress is definitely a thing I've noticed too. Though I played it a ton yesterday, I still only have some of my party 1/2 the way to level two and the others aren't to that "milestone" yet. But if you save up for magic items at stores, you'll be fine as that seems to matter a lot. Also, if you're like me, you got a lot of cruddy starting characters when you started the game and even if it holds back your Xp growth a little, you'll want to find better ones at various hiring halls around the world. Despite the fact they are called hiring halls, taking a character from one is free.
and for getting money, if the map isn't randomized, head south. I did and there are fire mephitis around. They tend to attack you solo and are easily driven away though they get two attacks per round and hit kind-of-hard. You scare one away, or better yet, kill one and they drop upwards of 100 a piece and they aren't shabby on experience either if you manage to kill it. You can find them on the road.
(I'm not sure if you noticed, but a lot of times you can say "more" after a little blippy sound to listen to more info, you can usually do that 3 times at a tavern, the buying drinks is just flavor as far as I know. Also, most shops, particularly in big cities, have more than just 3 things for sale and the cruddier stuff is on later pages, again... "more." and if you keep saying it it will give you the stats to a point and weight as well as name and price.
The temples can do special things for you, but only after you do favors for the respective God worshipped there. For example, you can get special bonuses, healing, and recently-added, free magic weapons by going to a temple after you have cleared out a dungeon that is a temple. For example, I know where there is an overgrown Srhine to Jupiter that is a dungeon crawling with Undead. If I were to clear it, I could then go to an active temple in a city dedicated to Jupiter and receive a special prize, though I think the prize is random, though you also get access to the pool after you please a god enough.
I hope that answers some of your questions and issues.
Also curious to how six Swords kids is different than the normal one.