I've enjoyed these videos (Full disclosure I've only watched one all the way through (1990 vs remake) but I have watched at least some of the others as well).
Thanks for making them.
Been doing a lot of thinking about optimal ruleset between EU and NA versions (I don't know the Japanese rules). Here's my thoughts so far:
i) NA monster body points - definitely the best and a big improvement in the NA adoption.
ii) NA Chaos Spells - also a big improvement in the NA adoption
iii) EU rule about not moving back through a square - makes no logical sense, but does enhance gameplay in my experience.
iv) NA rules on monsters picking up equipment and gold from a downed character are the best - EU rules I think it is way too easy to steal down characters stuff.
v) NA rules on visibility i.e. not just being able to see everything in a room.
vi) EU rules on when you can search from a visibility perspective. The visibility rules in NA version are a bit ambiguous by comparison and don't work as cleanly.
vii) NA rule on only being able to search for treasure in rooms. Rationale would be that anything that filters back the rate at which the heroes accumulate money is good, as I think one of the reasons people drift away from the game is their party becomes 'maxed out', and they lose interest without progression.
viii) Not in either rulebook but only one search for treasure per room for the entire party (again throttling back gold accumulation).
ix) EU rules on searching for 'secret doors and traps' as one thing. Rationale would be that having to search for 3 things (i.e. traps and secret doors separately) to clear each area slows gameplay down.
x) NA rules on searching for treasure in a pit trap - just a bit of fun! No secret door search rule though.
xi) For optimal effect falling block traps should be able to operate both in EU or NA style. Sometimes gameplay is best enhanced by the trap falling in the same square as the triggerer (like NA rule). Sometimes if it falls in the square with the arrow it best serves the quest (take Mellar's maze when in the EU version a player can become cut off from the rest of the party by the falling block trap with no opportunity to avoid this - lonely feeling trekking through a dungeon when a falling block trap has collapsed behind you).
xii) NA rules for disarming traps, as the EU rules are overpowered (Dwarf being able to disable any visible trap in a room or passage without it even being an action and the trap being 30+ squares away in the longest corridors is just silly). Sprung pit traps should still be able to be disarmed I think (as per EU). Sprung falling block traps should not though.
xiii) NA rules on potions including revival - helps players stay alive despite the tougher monsters in the NA version.
xiv) EU rules on selling weapons back eg. you can't do it like you can in NA version. Again rationale is throttling back gold accumulation.
xv) NA rules on spell scrolls - nice additional dimension to spell casting.
xvi) NA rules on no restrictions on each equipment card number. Also NA equipment like long swords is pretty important for building a beefier party longer term.
xvii) EU quest design standards on no greenskins and undead together - posted about this elsewhere but thematically works for me better.
xvii) NA rules on secret doors only opening when you step onto them.
Rules missing from both versions which enhance:
i) Moving next to furniture to search it - for those 'row of pit trap next to a treasure chest' occasions which don't work without forcing players to do this.
Thats all i've got for now. Let me know what you agree with and disagree with and why...