I'll add a little to what fenwaysouth and Chico Escuela have posted. If Ivy is your target then go for it; take the most rigorous load you possibly can without negatively affecting your grades. But do so because you plan on applying to Ivy schools with or without baseball. If you get in without baseball you can always try to walk-on. And if walking on doesn't work then baseball was never in the cards for you at an Ivy school. But perhaps that's OK because Ivy was your goal and you got in! But if baseball AND academics are important then HA D3's certainly should be your target as well. Then you need to really balance the workload in a way that doesn't affect your grades.
I support Chico's belief: I believe it is probably much easier to get into an Ivy school (w/ baseball) than it is to get into a HA D3. Ivy coaches have the ability to get ALL of their recruits through admissions--of course as long as they meet certain criteria--but I would bet that criteria is a bit lower for at least 2-4 out of 7 or 8 recruits. But of course those with the lower academics have to have really good baseball skills. The other recruits have to have really good academics (to offset those that don't) along with baseball skills coaches feel they need/want. But the key takeaway is this: if the Ivy coach offers, you will be admitted (of course you must maintain your current academics).
From what I understand, HA D3 coaches don't get a free pass for all of their recruits. In fact some may not get any help from admissions (Caltech). So those academics have to gain your admission without baseball.