Hardcore exercisers........I need your opinion

I do a basic tae bo workout three times a week. I am currently using the Billy Blanks "Basic 2" tape. It's a killer!!!! What I would like to know is can I do this more than 3 times a week, or should I be doing Soloflex weight work the alternate nights. I am trying to get back in the groove of working out since my summer/fall hiatus when I just didn't have the time to devote to it. I am wanting to firm and tone (and yes, loose a pound or 3), not become bulked up. I am hoping that somebody that knows much more than I do can give me some suggestions. The people here at Dave's seem to be so supportive, that's why I posted here. I should add that I am very physically active, since the Spouse and I farm. I hit the floor about 5 am and am not generally finished for the day till after 8 at night. My excercising is done after I get in at night. yes, I DO need to exercise, since there are muscles that don't get used, even in my brutal day's work. :>) Any suggestions will be greatly appreciated. TIA