I'm thinking of charging $250 for illustrations like these. Is that reasonable? They are easier to do than my typical illustrations so I don't really know what to charge.

If $250 seems like a fair price for you then it is fine. I'd personally charge more, but sometimes it's not a bad idea to have something that draws people in for the price.

I definitely think that it's a fair price and on top of that I think every artist deserves a tip after a well done job. TIP YOUR ARTIST, they work very hard!!! 👍🗣️❗

250 to 300 seems fair to me. (I'd be willing to pay that for an illustration like the ones you make) You could always up the price later too.

I would say set 'em at 300, they are definitely worth MORE imo, but if 250 is where you are comfortable, I think it's always better to add a little more as the tendency is to lowball oneself. (if it turns out no one is biting at 300, you can then run a "sale" at 250)

Oh the second and last one are so beautiful and look very detailed I honestly wouldn’t charge anything below €500 for something like this

I'd argue like $450 minimum honestly.