A general rule of thumb: The hotter the pepper, the longer to mature.

I am in Zone 6(ish) and my super-hots do not mature until the end of September.

Peppers that are good for salsas, but not set-your-face-on-fire hot are jalapenos and habaneros. Once you move beyond habaneros, you start to enter the super-hot range, starting at about Chocolate Habanero.

If you want to grow the super-hots, 1,000,000 Scolville and above, you would have Ghost Pepper (all colors), 7-Pot/7-Pod, Trinidad Scorpion (all variates) and, the king of them all, the Carolina Reaper, currently the hottest pepper in the world.

In my area I have found that I can sell the plants all day long however, when it comes to the fruit, nobody wants them. I end up selling the fruit to a co-op.

We start our seed for the super-hots around the 15th of December. Many of the variates take up to 20 days to germinate. Good luck with it and have fun.

Mucho Nacho is my favorite jalapeno. I also like Ancho 101 as a poblano.

Jalafuego is the variety of Jalapenos we grow. I really enjoy growing the super hot varieties, they are very pretty and colorful, but they don't sell. Jalapenos will sell, so I just grow them now.

Jay

You may want to add serrano peppers to your repertoire to satisfy people who want hot but not too hot. I sell them at 25 or 50 cents a piece, depending on how much competition there is.

Check out the local Hispanic markets and their ads to see what they are selling, because it's hard to compete with a trailer full from Mexico.

Hispanics are more into flavor than pure Scoville bragging rights, so don't concentrate on super-hots. The burn should not be so hot you can't taste the rest of the dish.

Fresh salsa -
Green Serranos for the crisp "green fire" bite they add to salsa and other dishes.

Green or red Jalapenos for a different taste in the salsa,

Chilacas ( a long black-brown medium hot chili)

Don't limit yourself to just a few types b/c often there is cultural diversity in tastes. Probably you want to certainly include jalopeno, anahein and pablano types but my sales in the thick cayenne and hungarian wax are my highest volume sellers.
The serrano, thin cayenne and small chili types just take too long to pick and although I grow them my picking method is to grab around the base of the plant and literally strip everything off to allow for later sorting. Using that method limits one to a single harvest. All of you who grow peppers know the time difference in harvesting. When a customer wants 3 bu. of hung. wax peppers I ask for a half hour advance notice. For Habanero types it could take 5x that much time.
You need to determine what your customers want and that includes shape and color. Surprisingly my primary thick cayenne customers want either all red or all green with no transition peppers. Often I cannot sell a red jalopeno and red serrano types are usually mushy. I have a few customers that specifically request choc. habaneros, but I believe a blend of colors sells better overall.