I'd continue the old show, counting the scripted finale as canon. All the core cast is the same, but they go to the other realms, and monsters are updated with current canon designs and power levels.
How would you nerd, make a new DnD cartoon?
Luke Ramirez
Christopher Gray
That hit a little closer to home than I really expected
Ayden Wilson
Back and forth between teenagers playing at the table arguing to the epic fantasy happening. Like you see a main charecter die and is rewinds over them arguing with the DM. Also each season is a new group of charecters and the dm changes.
Cameron Reed
Holy fuck I forgot that existed.
Zachary Rogers
I'd take every dime and put it into casting - hiring models that I get to fuck for years on end while I find the perfect actor until the project goes bust
Xavier Carter
Get the fucks who made Voltron to do it, have Presto be a girl disguised as a guy, and give Venger a better back story.
Also Tiamat can transform into a sexy babe.
Tyler Wood
>Voltron writers
No thanks I'm good.
Easton Turner
start off with oneshots where each episode is a different setting and different characters but played by the same players
and in the climax of the first season reveal all the oneshots took place in the same universe and a huge cosmic threat threatens all of them
Juan Wood
Throw out character sheets for eyecatches before and after commercials, like how FMA would have some bit of art that might give some small insight into a character.
Justin Kelly
Step 1: Set it in an actual D&D world, either a canon one or one built just for the show - the latter offers more profit with sourcebook tie-ins.
Step 2: Make the focus be on the adventuring party. Critical Role and its imitators are already doing the "meta D&D party" schtick, it's not going to compete well with them. Stick the viewers in the world that's been built and make them invest themselves in that setting, instead of being distracted by stupid memes and idiot players.
Step 3: Party has to be natives to the setting. We can't do the original cartoon's "isekai style" because the well's been poisoned by all the bad anime, and frankly we care more about the world if the characters themselves care about the world.
Step 4: Party needs to be a mixture of "classic" and "weird" races & classes. The stereotypical "humans with a token demihuman" party went out of fashion back in the 80s - it's why Greyhawk flopped and the Forgotten Realms took off. Give the party some variety, be it by embracing "new stereotypes" (Dragonborn Paladin, Tiefling Warlock), or truly unusual combinations (Dwarf Wizard, Elf Barbarian, Halfling Sorcerer). Preferrably a mixture of both.
Step 5: Go with an epic backstory. WotC came up with all kinds of cool campaign outlines in 4th edition - pilfer one of those.
Honestly... if they'd done this when 4e was a thing, I'd have probably used Scales of War as a basis for the plot. Nentir Vale setting, obviously. For the party... Human Warlord or Swordmage, Forgeborn Dwarf Barbarian (basically a less-grimdark Warhammer Dwarf Slayer), Winterkin Eladrin Warlock, Warforged Artificer or Wizard, Gnoll Fighter. That way, you've got a mixture of recognizable and exotic races, an obvious Token Evil Teammate/Token Heroic Orc, and a set-up just tailor made for to carry viewers from their rookie days to the epic final battle against Tiamat herself.