I stumbled upon two (2015) lists by Deltavector, with good rulebooks and good PDF rulesets. Deltavector is mad. He posted 114 rule review blogposts. He’s still married.

I will not quote his full list, but only mention some of his interesting choices:
(A few of the) best, according to Delta Vector:

• Infinity the Game. Great decision making that glosses over the annoying amount of special rules. Amazing art and production values. Good mechanics, crying out for a simpler WW2/modern conversion and a decent campaign system. A great game that rises above its flaws.
• LoTR:SBG+Battle Companies/Legends of High Seas/Old West/Gladiator. A surprisingly subtle and underrated game engine. Clean design that gave birth to a range of skirmish campaign systems. Easy to learn, and easily adapted with house rules – samurai and medieval mods are also available.
• Song of Blades/Song of Our Ancestors. SoBH is like a box of LEGOs. You spend more time making warbands than actually playing the game. SooA is a spin-off book for the wonderful world of the Quar. A whimsical, wonderful, coffee-table rulebook.
• Chain of Command. The pre-game scouting phase is awesome. The emphasis on “Big Men” and spotting gives a real flavour to WW2 gaming. I also like Sharpe Practice – pity I never play Napoleonics…
• Secrets of the Third Reich. A weird war game that is very simple, yet still more realistic than Bolt Action. Great vehicle building rules for using DUST and MaK mecha as well as random 1:48 models. 
• DBA. A triumph of simplicity and elegance. The only mass battle ruleset I have minis based for.
• Battlefleet Gothic. I couldn’t afford the models so I played with cut-outs made of ice-cream lids. Stood out from the usual Full Thrust clones. Even had a campaign system.
• Musket and Tomahawk. SAGA’s lesser known sibling. Interesting blend of familiar and new ideas for French and Indian Wars.
• Bloodbowl (free) I made my own board and spent countless hours playing against myself, in a solo league, using plastic counters as players as I was too poor to afford the official models. Awesome game. 
• Mordheim (free) Somewhat unbalanced, complicated, and showing its age, but still the benchmark for campaign skirmish games. I’d like to see an updated version with better activation (not IGOUGO!) and reactions.

(A few of the) worst, according to Delta Vector:

• Beyond the Gates of Antares (beta – free) Another GW-rip off. Warlord is trying to nudge further into the GW gravy train.
• Deadzone (beta – free) I may get the set for the terrain, but it’s missed the mark in trying to claim the Necromunda crown for Mantic. From the stats it looks pretty hard to actually kill anyone. After Infinity, most sci fi skirmish games seem bland.
• Warhammer 40K. 5th edition? I’ve lost interest in the codex “arms race” a long time ago and GW’s business practice slashed and burnt my remaining goodwill. 
• Flames of War. Not interested in replicating all the faults of 40K in 15mm WW2.
• Fields of Glory/DBM/Impetus. Yawn. Zzzzzz.
• Future War Commander. I found the rules surprisingly inaccessible and how the anti tank/anti infantry dice worked didn’t make sense.
• Rapid Fire. WW2 platoon level combat is a crowded market. It’s probably my 6th choice rules for this genre.