The problem is that indentured servitude is not a good substitute for slave labour. With North America, the problem was that land was cheap but labour was in short supply. So without a way of controlling the labour supply, migrants would finish their term of service then go somewhere that they could farm land themselves rather than working for someone else. Resistance to tropical diseases played a small part, too, but the biggest attraction of slavery in North America was being able to control the labour supply. Said control often being more than just the usual labour; what happened to slave women was horrific.
Given all that, I would expect strong and sustained pressure to legalise slavery, as it would be practised elsewhere (such as the sugar Caribbean). Slavery was banned in some North American colonies for a while in OTL, such as Georgia, but was later legalised.
If some ASB prevents the adoption of chattel slavery in North America, I'd expect that there's no boom in African indentured servitude. On a small scale, yes, but nothing like the rice, tobacco and indigo boomed which happened in OTL. More slaves get sold to the Caribbean and Brazil. Colonial North America is a place of small farms and small towns; somewhat more urbanised than in OTL, but much poorer and less populous than in OTL.