Don't know much about Daily Grams and such, but have used and really, really like Learning Language Arts thru Literature. They cover grammar (but we supplement with Winston Grammar and we found it was very easy to understand and to retain the info). I have heard Abeka's comp books are very good-but have not tried it. Hewitt has what is called Lightening Literature, but not sure if that covers grammar. Since I have been using LLATL the entire time I have been HSing (14+ years) and my kids do well with it-I have no need to try other programs. I am sure others will have some good suggestions. There is Jensen's Grammar, Jensen's Format Writing and a lot of other good programs (IEW is one that comes to mind) but it really depends on what type of student your son is and what he responds to best. LLATL is some workbook, some literature reading, has grammar and some writing (altho minimal). Sonlight has received raves about their Lang. Arts programs and you do not need to buy the whole kitten kaboodle to do it...just the sections you need. With writing, we have used a bunch of different things-nothing major and yet my 2 grads are doing great in classes at the college level...but and this is a huge one....they read and read and read good literature where they saw good writing daily. Essays, well that can be learned thru several different programs.... As I suggested to the gal with the math ?? above ya-go to Rainbow Resource (rainbowresource.com)and read all of their product reviews. Hopefully too, others will tell you what they like best. Whatever you do-do not panic. He'll get what he needs in plenty of time before graduating. If you have a co-op or group near you that offers writing classes, I highly recommend them. We go to a very small group in a gal's home once a week and do a mix of IEW and SL. It is fun to have the kids work as a group, individually and they have a blast getting together (so do the moms!). That is another fun option.
Not sure if I helped or not, but hopefully, some of it will be a blessing. Oh, I cannot stress enough that you need to read every book written on homeschooling High School. They are a vital source of info, ease your mind and have a lot of great ideas. I like Homeschooling High School by Jeanne Gowen Dennis, Homeschooling the Teen Years by Cafi Cohen, Home School-High School and Beyond by Beverly Adams-Gordon, Home-Designed High School by Diana Johnson, and Senior High: A Home-Designed Form+U+la by Babara Edtl Shelton.