Use it to humbly suggest something, showing you don't assume your opinion is the best or only one. For what it's worth, I think the blue design looks more appealing than the red.
Pro Tip 2/3
Softening Disagreement
It's a polite way to introduce a different opinion or disagreement without causing offense. I understand your point, but for what it's worth, I believe we need more data before deciding.
Pro Tip 3/3
Self-awareness
Shows you are aware of your limited expertise or authority on the subject. For what it's worth, as a newcomer, I feel the current strategy is quite effective.