I think the primary problem with the stratification of entities is simply because the stratification allows people to treat other entities with less respect than others. Like, choosing not to evoke a god, or even believing it is not possible due to the fact that they aren’t something to just summon for a menial deed… I mean that’s not the case for any entity, even a self-made servitor. You’ll get a lot more outta everything you do when you treat these entities, or anyone you wish to know period, with an equal level of respect. That doesn’t mean you do the same thing for all of them, but you approach them with equal regard to come at things respectfully.
I have personally interacted with Hecate in moments that could be considered completely disrespectful by most regards. However, my basis of respect is based solely on how genuine a communication is; I’d rather talk to a guy taking a shit on toilet over being at a 5-star, all-you-can-eat restaurant if the former is completely genuine while the latter is just trying to humor me with formalities. So based on that, I don’t have any need for an altar because it honestly does nothing to show more respect than me being just as I am.
Likewise, in the Hindu tradition, where Hanuman comes from, most any entity of an otherworldly nature is approached with an altar-like situation… at least in normal situations. However, all that is to say, while you would set up an altar for Hanuman, you would also set up an altar for a dakini, a rakshasa, a yakshini… even if the latter 3 are not deities of Hanuman’s renown, you come at then with the equal respect.
In terms of pre-requisites, I would say that you got a pretty decent level of energy sensitivity and control, have pretty good physical fitness and health, and can at least interface with otherworldly entities in a conversational manner. Now I do not mean that you have to hear words from them, but that you can readily receive messages well enough to perform automatic writing, use a letter wheel… something of that nature. Some people might disagree, but I feel that if you want to work with any entity without feeling like you’re winging it, you gotta have that basic interface.