Everything up to 13 had enhance rates increased (10 to 12 is still a bit of a chore, though). 13 and higher actually had rates decreased, and you can go up to +20 now. But don't hold your breath. Double booming is no longer a thing, and once a weapon is restored it's bound to you forever.
The stones in the seal shop guarantee a success going to +11, +12, and +13, but only apply to level 90 weapons. The +13 one treats your weapon as a restored one upon use, so it binds to you and cannot go any further. Still, it's insanely good and a +13 weapon is more than enough. If nothing else it will certainly last until you scrape together money for a higher one or get lucky yourself.
I mean you still had to have really good gear to reasonably clear certain Hero dungeons. If I recall it took me and my 3 friends with +8-10 lvl 60 weapons like half an hour to beat Hero Larken. His hero mode form had something like 11k def and unless my memory is failing me, 13k or 14k was quite the accomplishment at that time. It wasn't until lvl 70 gear that it became significantly faster, and lvl 70 gear was INSANELY hard to get. Endgame gears both now and then were never about clearing content, it was about speeding it up (except maybe Neamhain, but I've never done it). I bet you I could solo Lord Glas with +10 lvl 80 gear, but it's going to take me forever. Endgame grind is still entirely optional, but the difference now is they made everything pre-end game so trivial to acquire that the only real work you'd ever have to do to get gear IS the end-game grind. Obviously this has come with its own pros and cons.
I actually talked with my friend who got one of his friends to try the game for the first time yesterday. This person having come from games like Tera didn't think the game was able to be played with your feet like us 7 year veterans, and thought the difficulty was actually in a good spot. So clearly people that the difficulty neuter was designed for exist, but it still doesn't excuse the lack of an option for players to challenge themselves if they wish. In fact, I can't even comprehend what they had to gain by removing it. Hard mode/Hero mode stats, drops, etc were all already coded and developed. I honestly feel like it cost them more resources to remove the difficulties than if they just left them in, but I'm not a coder.
5 quickslots and giant HP/SP bar. That's most certainly pre-ignition, where spear Lann had NO i-frames. To play spear Lann back then you actually did have to be either ridiculously skilled or facetank.