Notes

Monster Hunter World is the definitive Monster Hunter experience.

Not to say that the game is perfect (it certainly has its caveats) but the strides that the development team have made towards making World as accessible as possible, whilst still providing series veterans with a more than solid entry, deserve nothing but praise.
The game looks amazing, environment and monster designs are (mostly) unique and appealing (there's a few duds in there), armour and weapons have tons of variation, the early game focuses and properly teaching new players instead of throwing them into boring gathering quests (and then expecting them to jump straight into tough fights with no experience), the new skill system is simple enough for newcomers to understand but deep enough for veterans to play around with for hours (especially after factoring in Charms and Decorations late game), (in combat) movement is weightier than before but attack and item use animations are sharper and snappier than ever, drop in/out multiplayer is a dream come true and the SOS system has actually become more useful and fun than anybody thought it would be.
I could go into into detail about every single one of those points^. I could talk about this game for almost as many hours as I've played it. But there's some stuff that isn't perfect too.
Combat, on the whole, is easier than before. Even after hitting high rank and taking on some tougher monsters, it's still easier than before. Why? Monsters act mostly the same (returning ones have the same attack patterns and speed) and everything deals much more damage than before. This is a result of the new movement/item use speed. Bigger monsters like the Anjanath and Radobaan (and even returning monsters) are easier because they hit the player (on average) much less often than before. This might be the reason some monsters have big 1HKO moves (even towards the end of low rank). Since players are getting hit less often, damage has to be increased to instil the same feeling of panic after a hit like in previous games. However, this is completely offset by the new item use speed. By being able to run around while downing a potion (unless a monster is going for a hard to dodge attack) you will probably never get hit whilst healing (combine this with the Ghillie Suit for maximum cheese). This might also explain the abundance of smaller, faster monsters in this game compared to previous games (although from a lore point of view, of course smaller monsters are going to be able to attack faster/more often, because that's how physiology works).
There's also a few instances in which dodgy hitboxes have caused me to take hits, but it's mostly minor compared with instances of the same problem in previous games.
Content-wise, the game lacks the breadth and depth of previous games but has more than enough to satisfy both newcomers and veterans. MH4U and MHGen both had "more content", but the amount of content that had been ported over to those games from previous titles greatly offsets that. MHWorld is possibly the first mainline game in the series to have built their entire monster roster, armour, and weapon sets 100% from the ground up since the series made the jump to PSP in 2007.

But now I'm just rambling. I know I talked about the negatives of the new combat mechanics for a while, but they really don't get in the way. The sheer amount of hard work and effort that went into creating Monster Hunter World has created a game in which the vastly positive changes to gameplay greatly outweigh the minor negatives that arise from them. For veterans, everything you loved is still there (with a beautiful coat of paint). For newcomers, there's simply nothing better.