We are getting married at a hotel. Do i need to offer an additional hotel block?

I think people can find places to stay on their own. Having said that, if you're planning to have a wedding website, you could make suggestions on available hotels.

I would make sure your guests know that there is a block at the hotel the wedding will be at (the convenience of just going up to your room after a night of dancing and drinking is huge). Otherwise, if guests want a cheaper hotel, they can use Expedia/Google/etc on their own to find one.

I would just put the block on your website and leave them to find their own hotel beyond that. And specify if there will be any perks included in that. Even if a cheaper hotel will give you a courtesy block where you’re not financially on the hook for any unused rooms, it’s probably not worth the hassle, especially if you’re in an area with a lot of hotels nearby.

We got married at a hotel and let people know there was a room block at our hotel. By no means did that mean they were required to stay at our venue/hotel but I also didn't book another hotel block somewhere else.

Nope, I don't think you need to offer an additional room block. If your hotel were super expensive, then my answer would be different. $200 a night is pretty reasonable

200 a night is a reasonable price. I think on your website you should try to do both. Offer the $200 a night to the people who are interested while at the same time telling them about a few hotels, Airbnb,vrbos, and motels that are close by. Don't spend a lot of time on this of course but the more options and information provided to everyone the better the experience.