The first two questions are purely subjective, although I would tend to say the WHFB wins out. But, that last one:>Would you recommend it to new players?
Yes. Yes. Yes, yes, a million times yes. It is simple, short, and to the point, yet still allows for strategy. Its minimialist. Its compact. But MOST importantly, its easy as fuck to play.
Let me explain; Prior to AoS, there was no "Beginners" Wargame. If you wanted to play, you'd not only have to buy, build and paint a army of minis, but also dedicate yourself to learning a 100+ page CORE Rulebook, along with a seperate army book of your army. Than you'd have to drag your army around, find another oppenent to play, and hope that he knew the rules as well as you did, less you spend a day and a half trying to get through a single fucking game, and thats not bringing money into the equation. And EVERY. GAME. Suffers this dam problem. They want you buy and read a 50 page rulebook, than assemble a whole army, and tha
With AoS? You have everything core wise on 4 pages, and anyone can download the specific warscrolls for units. In my town, literally no one played Warhammer. Plenty of people collected, but nobody dared play. That was until, Age of Sigmar came out; suddenly, we could help completely new people play a full game within a hour or so. That was mind-fucking-boggling.
So don't listen to people who say that other games are easier to learn; they're just plain wrong. Now, does that mean the AoS ruleset is good? Probably not. Infact, I know that when properly played, Malifaux and Infinity are far more fun. But, on the other hand, that takes far more time, effort and pure dedication to help build a community from scratch.
This is a fact: There is no easier game to learn than AoS