I have nothing against using a BowFlex, it can suit the needs of most men and women, with regards to staying in shape. It suits the average person. People here tend to downgrade this type of machine but everyone does not want to become a Mr. this or that. Just want to look fit and good in clothes (or some guy's, saturday night at a motel). But if Hardcore is the main goal than heavy, compound exercises would be the ideal way to go.
Training at home is an option, though a much better prime motivator would to be to train in a strictly BB'ing gym. Home training may involve expensive outlays of money to but suitable equipment. Though a chinning and dipping bar could produce very good development for a lot of people. Gymnist come to mine. Adding weight to those exercises makes it even more productive. Legs, at home, are another question. One legged squats or step-up (with added weight) may be the only choice.
Might try joining a gym for a few months (90 days is the usually short period) just to see if you like heavy training. If not, than see about setting up something at home. Search the net for ideas, though this site has some good programs on the front page.
Eat a suitable amount of protein based foods, based on 6 smaller meals a day.. Creatine has show very good results for a lot of people. Good luck.