My first question is what type of pear do you want?
Fine textured Euro pears tend to be slow to produce but worth the wait. Ayer’s Would be my top suggestion. To be honest, Euro Pears take so long to produce I haven’t had time to really evaluate many of them that are just starting to hit production. Seckel type Euro pears are excellent and a bit faster to produce then most but not the most disease resistant.
Asian pears are fast to produce and more manageable. The only one I would call bulletproof is Korean Giant which is a lower sugar aromatic type.
The hybrids are fast to produce but have a somewhat course texture. Kieffer is so bulletproof and productive you might find contempt for it. A Kieffer on standard rootstock might live 150+ years. Douglas, Duchess and Turnbull are great varieties and relatively problem free.