Homotopy theory based on an other space than the circle

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This question might seem philosohical. To me homotopy theory is based on two piece of information in the category of topological spaces : the circle $X = S^1$, and the reduced suspension functor $F = \Sigma$, then everything can be deduced from there : the homotopy groups functors are $[F^n X,-]$, CW-complexes are defined using homotopy quotient of spheres $F^n X$ etc. Is there a reason why no other homotopy theories are used, for example, for $X = RP^n$, or $X = K(\mathbb{Z},n)$ etc. Is is possible to have a homotopy theory also by changing the functor $F$ ? Or the only sane choice is the right adjoint to the mapping space functor $Map(X,-)$ ?