Toward a Vision of *My* Best D&D

As I work on my next campaign, I'm cobbling together all of the things I like from D&D and its close imitators, descendants, and retroclones to create what I am tentatively calling "my best D&D"--a "best parts" version, if you will that fits the play style at my table.

While I do enjoy D&D 5th edition, characters still seem a bit too superpowered for my tastes: nearly every class wields magic, or has a magic-wielding subclass, characters get new powerful abilities every level, etc. I would prefer something a bit more along the lines of James Maliszewski's "Pulp Fantasy D&D" aesthetic.

I will likely be using this blog as a set of notes to put together this Frankenstein of a game, listing the bits I enjoy from various other games, then paring these options down, removing redundancies until I get the core D&D experience I'm after.

For example, one recent-ish innovation that I like is 5th edition's Advantage/Disadvantage mechanics. It was an elegant way to dispense with a slew of charts and modifiers while keeping game play simple and fast.

So let's put that on the list first:

• Advantage/Disadvantage (D&D 5th edition)

As I read through my vast library of D&D and OSR games, I'll continue piecing through my options. Different topics I can already perceive are:

• Attributes: do we really need six attributes? Shadow of the Demon Lord makes a compelling argument for just four. But is cross-compatibility enough of a reason to simply go with the traditional six? (If I do keep the traditional 6 attributes, it'll be roll 3d6 and let the player assign as they choose.)
• Level caps? 
• Unified Experience Point mechanic vs. each class having its own XP chart?
• Attribute Modifiers: which edition should I use? I like the way Sine Nomine games assign attribute modifiers. 
• Proficiency: keep it? Ditch it?
• Skills vs. Ability Checks with Backgrounds
• Saving Throws: currently, I'm leaning toward "Saving Throws are essentially Attribute checks, with types of saves associated with specific Attributes," as in Castles & Crusades and D&D 5e. However, Crypts & Things remastered edition has an interesting system as well, where Luck replaces Saving Throws.
• Should there be some kind of Luck mechanic? Dungeon Crawl Classics and Crypts & Things remastered have some interesting options. Perhaps I should steal a page from the old Fighting Fantasy game books? Could a Luck mechanic replace Saving Throws? I was never really satisfied with the Inspiration mechanic in D&D 5e. Perhaps I might borrow Bennies from Savage Worlds? 
• Which version of Thief/Rogue, if any, should I use? The Specialist from Lamentations of the Flame Princess's (LotFP) is very appealing.
• How do we track Encumbrance in a simple, meaningful what that requires the least bookkeeping? Again, LotFP has a nice system.
• Gold piece or silver piece economy?
• How many different Classes do we really need, anyway? Aren't Rangers and Barbarians simply variants of Fighters? 
• Should Fighters (and their subclasses) be the only class that gets better at fighting with level advancement?
• How quickly should characters be able to recover from injuries?

So these are just some initial questions that are already bouncing around in my head, and I'm sure I'll come across others as I continue.