Wendy is very strong especially at the beginning of the game

[Primalflower]

Thought I would throw my two cents in here. If it is necessary to specify my perspective, I have 8,000 hours in the game. Wendy is a character that removes or greatly lowers the risk of many day-to-day encounters in DST, especially if you pay any mind to her extraneous items (Urn building, potions).

In the early game, some of the most common enemies you will face and most likely sources of chip damage are spiders, pigmen, beefalo, hounds, catcoons, batilisks, marotters. additionally if you're the adventurous/ambitious sort, Splumonkeys, cookie cutters, depth worms, rockjaws, powder monkeys. Save for rockjaws and arguably beefalo, Abigail either solos these mobs or greatly lowers the risk of engaging with them, especially considering you can return her (or just let her die) which will destroy aggro and likely give the player an escape opportunity. The fact that wendy loses all of these opportunities to take chip damage and thereby consume resources or die, means that she is inevitably going to be more prepared and have an easier time preparing for places where abigail can't help her as much, namely, bosses.

Beyond bosses, a weak point that wendy contains is shadow/nightmare creatures. Abigail cannot help her fight these. But, at the same time, Wendy takes only 75% of sanity drain from insanity auras and night time, meaning it is far easier to maintain her sanity, especially considering it has a rather high cap (200). 

Wendy has no resource gathering perks, but she is not worse than wilson at it either. She can still use all non-character specific methods to resource gather. I would argue in her case that the lack of resource gathering perks is much more of a simple inconvenience than a genuine hampering. I can understand differing perspectives on this, though.

You could argue that Wendy's perks, in of themselves, are not necessarily that strong, but simply put, she has amazing matchups. Her skills deal with so many of the most common enemies in the game and many of the most unavoidable threats extremely well, not even considering gestalt abigail and her boss killing potential. She is a very safe character and she is very strong.

To that end, I think Wendy's skill tree not necessarily powering her up to the max is perfectly fine and reasonable.