Estimate from people with xp?

If you played DnD 5e rule set in FGU, in pure out of the box default state for mechanical rules functionality. No extensions, and no GM or players doing anything of preplanning nor in sessions manually to make character class powers, DMG magic items, racial traits, etc. mechanically function.

What % of the stuff in the source books do you estimate is going to be ignored?

examples:
Warlock hexblade plays with whatever powers are on the actions tab for them by default.
Any stacking of A dmg reduction amount and A dmg resistance.(reductions and resistances do not stack, but one of each does)
fey ancestry traits for save and immunity calculations.
LoS that does not understand light levels of vision distance limitations
summon spells (just full GM manual make it happen as the player calls for it no player cast spell summon NPC to map and tracker and player can control automation)
Ring of protection? That some magic items just work out of the box and others do not, is there a systematic way to know what will and what will not? Liie so a GM could just only have magic items that do function by default in their camping


So from anyone with good xp in all this. Is there either A: a nice collected single stop location one can get informed about al that up front? you know like a product compare list of, has/does not have, between printed rules and FGU functionality?
or B: if smiteworks or Hasbro has not provided this info, what do you, from xp, estimate the % of rules are a table is tossing out of 5e if they just roll 100% out of the box FGU as is for whatever it just does without them needing to take some time to make it work.


Not trying to bag on FGU, trying to understand it. Finding out as you go what, by default, functions and what may require some player/GM plan time to make work, or just never will and requires some fiddly in session manual efforts is a bit of annoyance. It would be much more consumer friendly to spell all that out upfront for everyone.


Main need to know on this:
being a sandbox GM is its own lot of effort. making FGU just do what the book says it does is very likely to start getting out past my effort capacity for running sandboxes. So trying to get an idea of what i'd be giving up if my players can haver whatever of their class powers and spells they figure out making work on their own, and "attunement" to magic items is, whenever the player can make it work in FGU without me being the manual power of the magic item working, they are attuned to it.
Or also jus considering a world where the only magic items to find are the ones that mechanically function out of the box as is.

Our goal is to focus on roughly 80-90% automation of core rules. No one has done a full comparison that you are asking for; so there are not exact numbers nor a handy metric for weighing importance/usage of specific rules.

Regards,
JPG

When it comes to player actions, effects, and such, I honestly don't care. As the DM, it's not my responsibility to make sure the players know how to create actions for everything their characters can do. Now, I help them, and the players help each other. But its not my responsibility and if a player doesn't know (or set up their actions accordingly, or use their actions accordingly) and they don't get a benefit they should, it's not something I'm usually even aware of, and I'm ok with that.

For instance, the cleric in my party has a feat that when they heal others they get healed. One of the other players at some point setup actions for them on their Cure spells to heal others and to heal themselves. Just came up this past week that they had never healed themselves when they should of. Sure, for the rest of the session I tried to remember to remind them, but it really has next to no impact on the fun of the game.

Because 80% of all statistics are made up, or so I've heard, I would say that 80% of all character actions are automated. Sorry, *G* I know that doesn't help. But the way I see it, if FG is less than 100% perfect, then you have to verify and validate everything that's important, so, to me, it doesn't matter if it's 20% or 95%.

Another one?

D&D is not automated. Automation takes away from the game.

In regard to the metric system and weight we used the following base lines in the german D&D and AD&D (pen and paper) versions (1, 2, 3 to3.5, and I think, it is done for the 5th edition as well):

1. D&D is a game, it is not a simulation.
2. A game should be easy to play and is not just for professors of mathematics.
3. This in mind we didn't change the weights but translated just the word lbs. into the german pfd. (Pfund). Yes, there is a "slight" difference, but as long as all weights are under the same rule, the balance is guaranteed.
4. We did the same with the measure of lengths. One feet became 30 cm (100 Zentimeter are 1 Meter), 5 feet equals 1,50 m and 10 feet are 3 m and one mile was 1.5 km (Kilometer). As long as all measure of lengths are under the same rule, the balance is guaranteed.
5. Yes it is a trade off, but most of the players were happy with this.