Help! Which subscription is better to buy for Image to Image generation.

Friends! I would be very glad to receive advice, I want to buy a subscription to Midjourney, I thought to start with the standard version for a month for 30 dollars. My goal is to make illustrations, backgrounds and portraits for a dnd company. When I read the description, I found that some new function was released, which is only available to those who buy a subscription for one year. My experience in such tools is zero, so I want to ask.

I have ready-made drawings with sketches of characters on my computer, and I was thinking of loading them into Midjourney and using the image to image method, so that it would make characters as similar to the original as possible, but in different poses. Actually, will the capabilities of the standard version for 30 dollars be enough for this? Or do I need to buy the yearly version for 300?