Hello! Thank you for the feedback.
The green ring only gaining experience when hitting the dryads is an oversight that I'll fix in the next update. Where/what enemy did you notice the Magic Lens(HP/MP viewer) not working? Also, do you remember which hole in the cave you got stuck in?
Titania will become recruitable again in the future, but I'm deciding on the conditions for this as well as other enemy characters. The wisps are still a bit of a WIP, but keep in mind that they are not supposed to be easy to reach right away.
As far as the difficulty is concerned, there are going to be parts of the game that are harder than others, where you have to think or strategize to get through, instead of just bluntly pushing forward. For example, that first small area on the tree becomes pretty easy if you simply do not go there first, and bring some allies with you beforehand. If you attempt it and notice it's too hard, you can just go to the menu and return to the castle. The gemini trap spell, though less ideal, can also be a big help in getting past that first small area, if you have no allies.That is not to say that I'm not still tempering the difficulty however.
I have several areas planned, but after the forest area I will continue developing the fire and ice areas that I've already started. Ideally, I would like to finish this game this year.