I have been doing tons of research on this very subject.
it is important to know your market or what it will be.
Will they be exported into the US, Japan or Europe ? each market has certain post harvest requirements.
If the mangoes are to be sold to local market, your choices are wider.
The mango that keeps coming up favorite in all almost every trail is the Keitt mango.
these benefits of Keitt for commercial export:
Very long shelf life
Very productive
Healthy Tree
Preferred mango shape and size.
Can be picked green, and still ripens well
Fruit quality is good-excellent.
Other varieties I am considering for export.
Osteen
Rapoza
For local, so many potential candidates .
the idea here would be to have an extended season, so Early, Mid and late, the mangoes listed above are mid-late varieties.
Early candidates I am looking at are, Rosigold, and latest would be Neelam.
You need to take a look at your climate, some varieties will do better in rainy weather, than others.
In a semi arid farm with well drained soil, using drip irrigation, you could probably grow any variety of mango with success. which is my situation.
Heavy clay, and lots of winter rain, your options will be limited.
Anyway MY list has these varieties, which may change, depending on what my market would be, it may end up being 80% of Rapoza or Osteen for export market, and rest 20% spread on all the others for local market. or maybe I will concentrate on all early and late varieties to take advantage of off season mango prices.
Early: Rosigold, Glenn ( Because of earliness and quality )
Mid: Maha Chanok, Lemon Zest, and Coconut Cream. ( because of quality )
Late: Rapoza, Osteen. Neelam ( Rapoza or Osteen, for export & local, Neelam, being latest )
i know that some of the above varieties, may extend later or produce earlier than what is listed as its season.
Notice I do not have Keitt, this is out of preference, this seems to be what everyone is planting, and well I want to be the black sheep.
By the way, I do desire having a genoplasm reserve, and have at least 1 tree of each known good variety, non of this would be lost profits, as these mangoes could also be sold to local market.
One more thing, Will you be using normal density, high density or Ultra high density? Organic or not?
On my "dream farm" I am thinking of using High density of about 500 trees per acre ( 3 X 5 meter spacing ) more spacing for genoplasm reserve trees.