I'm sure I'll run some games of D&D 5 to get a feeling for it. There's a lot of good stuff in it which I, on first reading, prefer to my traditional go-to, Labyrinth Lord. I'm open to the idea of this becoming my standard base of rules to build from, and it feels like a very solid foundation, at that.(http://the-city-of-iron.blogspot.de/2014/09/d-5-how-i-would-use-it.html)
In the comments, the esteemed Carter Soles posed the question of what exactly these preferred elements of the game are. This post is in answer to that question.
So, some things I prefer about D&D 5 when compared to Labyrinth Lord.
Unified Proficiency System
Among all the cool new ideas in D&D 5, this isn't one I've seen discussed a lot (that merit must go to the "advantage / disadvantage" system), but is without a doubt my favourite mechanical innovation. In older games there's always been the concept of proficiency with armour and weaponry, whether it was embedded in class descriptions ("magic-users can only use daggers and cannot wear armour") or made explicit through a system of weapon proficiency (a la AD&D 2nd edition). There was also some more muddy territory around who can use what tools -- for instance, can any character use lock picks or are they the sole domain of the thief class?
The D&D 5 approach to proficiency wraps all this up, along with a greatly simplified version of the later-edition skills system, into a single proficiency bonus which advances with level. A character is either proficient with something -- in which case he or she gets to add the bonus -- or not. There's no skill points to fumble around with and the rules are deliciously broad: proficiency with a tool, for example, allows the player to add his character's proficiency bonus to "any ability check you make using that tool".
I can also imagine stripping things down further at times and simply saying that a proficient character can do X while a non-proficient character cannot. No roll or bonus required.
Backgrounds
Now these have bee touted as a universally great thing and I'm not one to disagree on that point. Reminiscent of the AD&D 2e "kits" system, but completely class-neutral (your cleric can have the "criminal" background equally to a rogue), backgrounds are great packages of flavour for new characters.
To my mind (though obviously not to the designers of D&D 5), the backgrounds system completely eradicates the need for more than the four core classes. Want a barbarian? An outlander fighter. A bard? How about a rogue with the entertainer background. A paladin? That's clearly a fighter with the adept background. And so on.
Again, simple, flexible, and packed with flavour.
Admittedly, choosing a background adds an extra step to character creation, which means extra time. This stuff inevitably comes up at some point, though, anyway, in roleplaying situations or when the referee needs to know which characters could conceivably know or do a certain thing. Giving each character a single word background ("sage", "sailor", "urchin" etc) adds heaps of flavour. The flaws, bonds, etc could even be ignored initially at char gen, to speed things up.
Equipment
I love the equipment section. Simple guidelines on selling treasure, trade-offs for light vs heavy armour types, weapons distinguished by various properties (this is very much lacking in LL), pre-selected packs of adventuring gear, broad guidelines for lifestyle expenses and hazards / benefits, detailed equipment lists, and even a random table of trinkets! Good, very usable stuff.
Schools of Magic, Divine Domains
Obviously, I like magic in D&D to have a bit more depth to it than the simple B/X approach. The Advanced Edition Companion for LL goes some way to providing the kind of elaboration I like, with the addition of another type of priest and another type of magic-user, but I'm always eager for more of this kind of thing. My feeling is: why stop at one alternative?
D&D 5 provides a really nice system here: casters must choose a specialisation. Clerics choose at 1st level and magic-users at 2nd (I think... or was it 3rd?). Each class has a choice of 8 or so specialisations, each granting some unique abilities (and, in the case of the clerical domains, a different spell selection).
Obviously, for someone of my proclivities, this still doesn't go far enough, but it at least provides a nice foundation for further work. Suffice to say, this is by far my favourite implementation of such things in any edition of D&D so far.
Downtime
Tying in with the guidelines for lifestyle expenses, in the equipment section, the short section on downtime activities on p. 187 is delightful in its simplicity and usability. It even includes rules for learning new languages (though I note it doesn't extend to skills) -- something which I've never seen done to my satisfaction in D&D before!