Federal Police Agent here, and currently working at the Immigration Department.
First of all, you don't really need a lawyer to begin the Naturalization process. You can handle it yourself, in any Federal Police Station, but, it's up to you.
About your doubts:
Usually staying more than 2 year outside Brazil makes you lose your Permanent Visa, and your CIE is collected. Meaning you can stay up to 23 months aways, and still be considered a Permanent resident. BUT, for Naturalization we analyze how much you actually stay in Brazil. Since we look at your passport and all your entry/exit in Brazil, it may be that the Federal Agent that analyzes your case understands that you don't actually live here. You can still begin your process without living here for a year straight, but I wouldn't recommend. And, sorry, there's no way to bypass it. Also, we give our opinion about your background, visit your house and etc, but the Ministry of Justice has the final decision. So you can appell to them if you disagree with the Federal Police's opinion.
The test is still applyed. It's not for some cases, but I don't think you fit in any of them (would be residents for more than 15 years, or people from Portuguese speaking countries, and a few others). The test is not difficult, but you'll have to read, write and listen in Portuguese. Grammar mistakes usually are not an issue. We just want to know if you can understand our language.
You might want to take a look at the law 6815/80, wich regulates Immigration affairs in Brazil, for more information.
Any other questions, feel free to ask, here or PM.