Frogmama has an amazing selection of wonderful, comfortable and super cute mei tai carriers, but the choices can be a bit overwhelming at times:)  I will try to help narrow things down for you.
Both the Freehand and Babyhawk can be used with newborns, but if you have a bigger toddler I would go with the Babyhawk Toddlerhawk.
 You can also use the Toddlerhawk with a newborn by just rolling up the bottom.

If you want a carrier with a shorter panel and something lightweight and compact I would go with a freehand.

If you want something with a little more padding and with a taller panel and headrest go with the Babyhawk.

If you are on the plus size go with a babyhawk or toddlerhawk with XL straps.

The great thing about mei tais is that they are really customizable to each person to get a great fit. You can roll or unroll the panel to make it shorter or longer. You can tie it higher or lower on your torso. And the straps have an ability to give a perfect fit to most all people as you are not limited by buckles/adjusting straps.
I just made a video comparing the Freehand and Babyhawk mei tais here.
Frogmama's New Support Rating Frogs:)
  Is for a carrier that offers a small amount of support- good for infants and lighterweight babies

  Is for a carrier that offers a moderate amount of support suitable for babies and toddlers

  Is for a carrier that is very supportive and will comfortably support an older child ages 3-4 years.

Freehand
Babyhawk

If you are still having trouble feel free to give me  a call for help:)
             (530)921-8855