You guys aren't alone. But be careful about so blatantly saying that they 150s is bright....as the guy who made/designed the 150s created this very public post:
"Hear the warm voice feel very comfortable, hear the bright voice feel harsh, if you are so then your ears have been damaged."
Basically, if you think the 150s is bright, your ears are apparently broken LOL.
Anyways, I too was underwhelmed by the 150s, so much so that I had pretty much considered them to be a throw-away. But in retrospect I'm actually really glad they weren't great, as that forced me to do a bit of a DIY.
So, If you want to make the 150s far more enjoyable, and you're feeling a little ambitious, I did a fairly simple mod which honestly turned these into something I enjoy listening to on a daily basis (as opposed to how fatiguing they felt before).
This will require you to open the buds up, and firstly remove the tuning foam which blocks the venting holes on the shell (there's no foam or cotton on the back of the driver). Now, the next part I've only tested with a Hiegi donut foam, but of course you could try it with one of the included donut foams too (but I can't guarantee the same results)
What I did was to cut a little wedge out of the foam, which will give you access to cut along the elastic centre-line (in order to have 2 roughly equal pieces to use). Then you'll need to test fit the foam behind the driver, and cut just enough foam away from each piece so that the end pieces meet neatly, but don't overlap one another. Tuck the foam in, but don't bother with gluing it in.
I don't think this is the ultimate mod for these buds, but it certainly makes them more enjoyable. Using them with my Shanling M2s + Fiio A3, with bass boost turned on (buds always need a little extra help) the 150s now feels pretty well-balanced. The next step would be to experiment with tuning foam and cotton to really refine the signature.