Capped Instances: Please no. All this means is more equipment that has to be stored. Instead of gear for your level 50 job, you now double it up for your level 30 job (or tripple if you want Level 30 and Level 40 cap areas). This also runs into issues with 'jobs'. A Level 30 area would mean in essence, no job, just classes? Then the fun of having to maintain a bunch of different action slots and macros to represent what is available at those capped levels.

I do not see how this is fun.

Open World Dungeons: The worrying concern I have about this is the camping competition. Will I have to try and provoke faster than 5 other LSs and 3 other RMTs for the special NM? WIll I have to worry about other people trying to hurt me while I fight? If those are not valid concerns, then I can see promose for Open World. But if those turn out to be real concerns, then I would be worried.

Why not just have dungeons that allow a variable number of people to enter (1-24 with alliance support), and have the monsters 'scale-up' as appropriate. So Toto-Rak would scale up to level 50 if only level 50 people went in. (Even if monster scaling up was 'simple' in the sense of stats only, and not skills/behaviour/names).