1) Maps can be useful. Consider maps as an added bonus on top of exploring a regular catacomb. A map with +2 to evil presences will guarantee at least 2 evil presence that spawn in that whole map.
Maps are relatively the same with the exception of a few things: monsters in a map are not randomly generated. they follow a pattern based on which map you enter. This can be an upside or downside, depending on the map you choose to explore.
2) You will end up hitting a wall at some level. It's possible to make it to the master quest with gear that drops, but I would recommend buying gear off the MP or making a post to find affordable gear to climb a bit faster. The less that you have to go to town and regenerate life/mana, the more fun and engaging
3) Going back and forth from the catacombs to Town isn't "really" a downside. The downside being the more time spent in town, the less you are killing monster's and finding loot or gaining exp.
The fishing well you can find exploring adds a bonus to the tier of fish that can be caught, maybe someone else can elaborate more on this if fishing interests you. But the more important part of finding a Well is that you can drop "White" item's in them to fight a more powerful monster. Item's that have no stats on them of any tier can be dropped into the well and return an item with stats on it. This is a great way to find valuable item's or you may choose to sell these White item's on the marketplace for FG. The higher tier white item's you find have more value than the more abundant lower tier white item's.
There's a lot more to it than the things I mentioned in my post, if you have more question's I'm sure the community can help answer some for you or you can pm me. The best resource is
's profile in all honestly and my opinion

he has price's of the current market and a pool of guide's if you have the drive to research more about the game.
For example, this guide tells you which map spawn's the pre-selected monster's of that map type and includes their unique abilities:
https://i.imgur.com/4F4iEGc.pngThis post was edited by JonWon on Jun 1 2022 01:57pm