I think the low level experience could be better so a dedicated arc with more actual content would make it way better. I would set the needed level to 10 since after the welcome to mission line and a bit of grinding you can hit lvl 10 fast.
A way bigger gap are lvl 35 to 40 and 45 to 50.
Since I made a post for recalculate daily mission xp Link to the Post here the overall level experience would be way better. I think there are too many missions dropped because they aren't worth the time doing them because the amount of xp they give. And any mission should be worth to be done because someone spend time creating them.
What I personally miss is the lack of content after your daily missions. Since you get your daily missions from the village mission desk and only there, why shouldn't we get other missions from different villagers (npc) as well? There are some open world missions as well just to be clear.
For example a local fisherman that gives you x missions to catch different types of fish for x amount of xp and ryo. And maybe one weekly mission to catch a legendary fish for big xp.
Same as gathering missions like the medical III dailys, the time you need to complete the mission is huge if you aren't rich and need to do it from scratch, so make this kind of missions not a daily but maybe weekly extra mission.
As for content I would love to see instanced pve content like bosses with random loot tables you could join with a group of upto 4 ppl to try and kill a boss. Entrance fees could be big amount of farmed items or special boss coupons earned during events or traded for items.
Ah and for the grinding guys out there, the mob xp after lvl 30-60 should be set to a realistic amount. I could do some math for calculating mob xp if needed.