You have several options, each of which will have pluses and minuses for your list. I will put the school district so you can have that for reference. You may find
https://ed.sc.gov/data/report-cards/ helpful to get a general idea about schools. Those report cards can sometimes be misleading but they give you a general idea of school performance over time.
First, I wouldn't rule out living in the Pickens County area around Clemson. The high school there, Daniel (Pickens County Schools), is very good academically. I'm not sure about chorus but they do have an active marching band and sports program. Clemson is close to Seneca, and you could be within 10-15 minutes of the LDS church there. For hospitals, you could work in Seneca (10 min), Easley (15 min), Anmed North or Main Campus (30 min), Greenville Memorial, or St. Francis (40 min).
I don't know a lot about Seneca High School (Oconee County Schools) other than they have a pretty good marching band. Academically I think they are pretty average for this area. Living there would be close to your church and the hospital in Seneca. Most other hospitals would be an extra 10 minutes over the times for Clemson.
Pendelton would be a consideration (Anderson District 04 Schools). The high school there tends to be pretty good. They won the state AA marching band championship this year and normally have really active sports programs. Pendleton would be ~15 minutes from the church in Seneca and 20 minutes to the one in Anderson. Pendle ton would be ~15 minutes from the hospital in Seneca, 20 minutes to Easley, 20-25 minutes to Anmed, and ~35 minutes to Greenville Memorial and Saint Francis.
The North side of Anderson in the Hanna High School attendance zone (Anderson District 5 Schools) would be another option. Hanna tends to be good to excellent academically. They don't have much of a band program - not sure about choir. Hanna tends to have a very active sports program. Hanna is a really big high school, a plus for some and a minus for others. You want to make sure that you are in the Hanna attendance zone in Anderson, though, as the other schools in Anderson are not as good academically. You could live very close to the Anderson church and close to Anmed as well.
Just north of the Hanna attendance zone, you have the attendance area for Wren High School (Anderson District 01 schools). Wren tends to be very good academically. They have a very active band and choir program. They have an active sports program but they don't win many football or basketball championships. The Wren attendance zone covers a huge area. You distance to church would be 15-30 minutes depending on where you lived in that area. Depending on where you were, it would be kind of in-between Anmed and Greenville Memorial. That could be an advantage if you wanted more options. It is kind of a rural area, which could be a plus or minus depending on your desires. The Wren area will be 15-30 minutes to Clemson, again, depending on where exactly you settle.
Powdersville (Anderson District 01 schools) has a very good to excellent high school that opened a couple of years ago. It was a split from the Wren attendance zone due to growth in that area. Powdersville has a very active band and choir program. Powdersville would be convenient to both Saint Francis, Greenville Memorial, and Easley hospitals. It would be 30-40 minutes to Anmed from there. It takes ~30 mintues to get to Clemson from there. Powdersville is also convenient to downtown Greenville. The main drawback to Powdersville would be the distance to church. The one in Berea would be 15-25 minutes away on a road full of red lights.
One last consideration would be Easley (Pickens County Schools). The schools there are pretty good. Easley covers a pretty big area but depending on where you lived it would be 15-25 minutes to Clemson. The Easley hospital is in Easley, and it would also be close to Greenville Memorial or Saint Francis. Easley would be ~20 minutes from your church in Berea but that would be going on a backroad without redlights. If you were on the NE side of Easley, you could be as close as 10 minutes to your church, at the expense of increasing the commute to Clemson to more like 30 minutes.
International Baccalaurate (IB) in high schools, in short, is a college prep program. If you are familiar with Advanced Placement (AP), it is a similar idea but is implemented differently. Most of the schools in the above list will offer IB, AP, and/or college dual enrollment courses for advanced students.