The thing is, the old question of “which is strongest/fastest/best” doesn’t have a one size fits all answer.
As every situation and its energy (motivations and emotions) are different, so will different entities do better in different circumstances.
Search for “strongest spirit” to see for yourself, that one get this same answer over and over again.
You need to break down what you want and how, then do the research - read through grimoires like Corwin Hargrove’s Goetia Pathworking with modern descriptions of entities abilities, that more to the point, many here including myself have found work - then make your choice of one or more that fit the energy and work from there.
Tip: It’s worth reading the new threads every day. Many you can skim over, but you never know when something very relevant will come up, and it can become another source for synchronicity to bring you the info you need.