Credit line increase – anything I should know?

I bank with BofA and I have a customized cash rewards card that I got when I was a college student a few years ago so the credit limit is now a little low for my spending. It’s currently $2,500 and I typically use about half of that each month but I recently became aware that it’s not good for your credit score to use more than 30% of the limit. I want to request a credit line increase but I’m not going to spend more, I just want to use less of my limit. Is this a good idea? Or would it be better to apply for a different card to split my spending and utilize the cash back bonuses better? Or I could do both? Any suggestions/tips/advice is greatly appreciated!