Aside from making the campaign feel more like an open world, I run my OSR games this way because mechanically it allows players to decide on the "difficulty". A Lv 5 group storming a Lv 1 dungeon is nice change of pace from time to time.What is the goal of offering the choice? Is it just variety, or is there a in-play reason there are X dungeons that need to be explored? On that note: are the dungeons there to be explored, or cleared?
Variety. Sandbox. A chance to get more level 1 treasure and XP. Do they risk level 2 or go hit level 1 in dungeon B?What is the goal of offering the choice? Is it just variety, or is there a in-play reason there are X dungeons that need to be explored? On that note: are the dungeons there to be explored, or cleared?
In that case I would make them pretty different. Maybe the tier 1 dungeon is very dynamic with constantly shifting internal factions so it is fun and worthwhile for the PCs to revisit it. But maybe the tier 2 dungeon is a death trap known to be full of really valuable treasure. Do they dare, especially when they are really hard up for cash? And the tier 3 can be something like Dragon Mountain with a powerful figure in charge and maybe the PCs go there early to beseech it and go there later to kill it.Variety. Sandbox. A chance to get more level 1 treasure and XP. Do they risk level 2 or go hit level 1 in dungeon B?