Have You ever considered adding an options button to turn off quest markers on the minimap ? Honestly it completely kills exploration element for me whey You enter a new map and it already points where to go, and making it optional should be a win win for the quick runners vs normal ppl . That is a part of older games I really miss like in D2 , being free to take a wrong route find some other staff , I feel in current times everyone wants to take the shortest route possible to go further , but why create good looking maps when You encourage player to skip 80% of it while pointing where to go 
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Kinda yes & no. I agree/accept that some people enjoy the exploration part of it, but given the fixed nature of the campaign that can only last for so long & because of the linear & non-randomised nature of the campaign maps it’s not difficult to work out where you need to go. There just aren’t any “wrong routes” (apart from ~3 zones that don’t have a quest in them & that you don’t pass through to get to your destination).
I’m not saying it’s a bad thing to do, just that I don’t think the value is as high as you might make out.