A Mei Tie sling is good for hip development as it provides a wider seat. Please be sure you have a really good look online at correct leg positioning. Better still, go to a Sling Meet.
Tie all slings high, so baby's head is "close enough to kiss" as has already been mentioned by PPs.
I'm so sorry to hear of your experience toddler 
Regarding stretchy wraps - Kari-Me is a stretchy wrap, but is one of the stretchier ones. This is NOT a good thing as it makes it much harder to tie tightly to give correct spine and neck support for your baby.
A soft wrap with some stretch, but not too much is preferable. Test the fabric before you purchase. It should stretch one way, but less the other (think of the warp and weft of the fabric) Moby are a good brand, as are Calin Bleu - they make fleece stretch wraps.
Baby should sit high. His head should be below your collarbone, between your breasts. "Close enough to kiss", is the mantra. Never cover baby's face or head, and check on baby regularly - be constantly aware of their movements, noises and breathing, especially in the early weeks. This soon becomes second nature as your mothering skills develop 
Slings are truly wonderful for bonding, and easy transportation on buses etc.
Be armed with the correct information on positioning, and know where to go to ask for help - SLING MEETS are amazing for learning carrying skills.
Accidents do happen, but they can happen in any given situation, sling involved or not. Be aware, and be well researched
Babywearing when done correctly is enjoyable and hugely beneficial.