Yeah, the A10C requires a HOTAS with a lot of buttons. The F-18C seems to require less but I don't know yet.
You can buy the F18 while on a pre-purchase discount, save 20 dollars. Before you get into A10C and Mig21Bis, do some research on yt, there are a lot of dcs videos of them.
Edit- Altho the F18 will be amazing when completed, having only dumb bombs and rockets might not be interesting for a long period, until it gets the smart weapons. If you want something with GBUs, Mavericks, JDAMs, then the A10C is just right, before the F18 gets them.