The way it looks like to me is that there is only a couple best configurations and they involve a lot of dump stats.
Define "best". Here are the four characters I made for Encounters:
- Hill Dwarf Fighter dual-wielding handaxes: 15/10/14/10/12/14 – He's a not-entirely honest merchant and has made good use of that CHA in the 4Es of both HackMaster and D&D. He'll take Heavy Armor Mastery at 4, raising his STR to 16 and significantly reducing his incoming damage.
- Human sword & board Fighter that acts like a cleric: 13/16/14/12/12/8 – I'm generally opposed to dump stats since my dice rolls tend to suck enough with penalties, but he is very timid, so it fits. Since he has some of the skills of both his father (human S&B fighter) and mother (elf ranger who heals with herbalism), I was forced to go with a finesse weapon so he'd be good with a bow and sword. His human feat is Healer, and he will also be taking Heavy Armor Mastery at 4.
- Human Thief: 8/16/12/13/12/15 – Here, once again, the dump fits. She's not overly strong because she carries everything in her merchant's cart rather than on her back, and for years had Farga, my dwarf fighter, as bodyguard and apprentice. She is slightly more honest than he is.
- Half-elf Warlock (character I'm playing currently): 10/16/12/10/12/16 – She has two ways of dealing with problems: seduction (thus uses lots of DEX and CHA) and fireballs. She makes her way through life as professional arm candy, so any obstacle she can't talk her way past she blows up. With 1d10+3+10' push as a cantrip and Shatter prepped, she's as much fun in combat as she is in town.
All but the dwarf come from a book I'm writing (but in games and a short story I even tie him to them) so I have their backgrounds, appearance, abilities, and personalities
very well flushed out, and that determines their stats for me, but I naturally have to compromise with whatever system I'm adapting them to. What that means is that they each
have the best stats I could give them within the limitations inherent in all class-/level-based games. I agonized over every point so much that settling on stats took ages, and weren't actually finalized until near the end of the process.
One of the things I love about 5e is that the game's math no longer requires you to have a 16 in your attack stat and won't allow you to get an 18 at level 1. The 16 DEXes I used are only because I'm tired of characters dying all the time 8o) Last season my wife's cleric hit 0 HP several times in the first few weeks (which stung a bit since I was the GM), and this season one of the PCs actually
died in our first encounter. It may even have been the first NPC attack that killed him, but we don't remember for certain.
A small rant while I'm on the subject: HackMaster and GURPS are both well known for the lethality of their combat (though HM5e isn't quite as bad as 4e), yet I've seen more characters go down in the short life of D&D 5e than in a decade of playing GURPS and HM. This edition is
really scary sometimes. Even HackMaster 4e gave most characters a 20 HP "Kicker" at level 1, and in 5e it's your CON score instead. (But that's offset by penetrating dice rolls which can result in massive damage from a d4 dagger; I did around 40 damage with a 4d4 fire beetle once). From behind the screen I'm always paranoid about encounter design since a few bad dice rolls can lead to a party wipe (and before anyone says the oft-reviled word "fudge", I roll in the open so my players know for certain that I don't cheat). Fortunately, since I only run D&D at Encounters I never have to generate combats from scratch so that makes it easier, but in a home game I'd have to houserule in CON HP kickers for the sake of my own sanity.