Kindred is weak.
I have over 20+ mastered level 5 champions, Kindred being one, and I have had some monster games where i've dominated, even with some quadra kills, but overall, you tend to go more negative in most games than positive with kindred.
Kindred is one of those champions that honest to god needs to be ahead to succeed or else, their damage sucks, their impact is useless outside of the ultimate.
The real weaknesses is Kindred's attack speed being ultra slow, that needs a major buff, and also their mana sustain is terrible until you get hunters potion which solves the issue as it does all other junglers, but the attack speed for Kindred is crazy slow, even with attack speed runes.
Kindred's damage is not that good unless you proc your 3 hit on the E skill, then it does a huge chunk of damage but since you attack so slow, you are putting yourself at risk to get that major damage off. So, riot needs to tune their attack speed up a notch, then I think Kindred will be awesome.
Another weakness is how squishy they are. Sure, there is tons of other squishy junglers, but given the above weaknesses already, this hurts Kindred.
I love the champion, I wished they got some buffs, I'd so play them more as I love the design and look of the default skin, but I just can't stand being useless cause Kindred is very dependent on their team as well where other junglers can just carry so hard.
So I'll happily continue playing Vi, hecarim, and my favorite Ekko, Kha'zix, and Udyr, maybe Eve.