I would say that if you have an eye for detail when filling forms, and if you have a good knowledge of the forms and the process, you can probably do it without much difficulty. Most of us here have done some, if not all, of the process ourselves. The VJ guide for a spousal visa here can help. Here are a couple of facts:
1. Even if an attorney files your paperwork, YOU STILL HAVE TO DO THE LEG WORK. You will have to compile all the info, etc. and provide most of the documents.
2. Attorneys cannot speed up the process at USCIS.
3. Some attorneys make mistakes. In our case, our attorney failed to send required documents to NVC. As a result, it delayed my wife's spousal visa for 3 months. We immediately took charge of our case, and we completed the interview process, our I-751 to remove conditions, and my wife's N-400 citizenship processes......with no issues.
Of course, the choice is your choice. You should strive to be an "A" student of the forms and process. I think that the Visa Journey community is a great source for accurate immigration info.
Welcome!!