I am not as old as you (I am in my early 20s), but I have come to the same conclusions independently.

If an interest or proficiency in rationality is related to cognitive or personality traits that show sex differences in mean or variance, such as systemizing or Openness to Ideas, then the pool of female rationalists would be lower that the pool of male rationalists. Consequently, barring polyandry, not all male rationalists can date female rationalists.

Yet even though a female rationalist might be a good match for a male rationalist in many ways, it is not self-evident that a male rationalist will only be compatible with females with a similar interest in rationality. What types of women he will be compatible with is an empirical question, that can only be answered through experimentation (i.e. dating women with different types of personalities).

Even though many male rationalists might think that they would be ideally matched with someone who thinks like them and inhabits an attractive female body, in practice, this may not happen. In females, an interest in rationality may be correlated with other masculine features, personality traits, body language, etc... which may or may not be attractive to the male rationalist, depending on the degree. While commonality due to similar thought processes might increase compatibility, there might be less chemistry. Or the chemistry might be just fine, and they might drive each other crazy for other reasons, especially if they have unresolvable philosophical differences and they both have a need to be right.

If a male rationalist cannot date a female rationalist, either due to scarcity or incompatibility, there are other more common types of women he might be quite compatible with. Specifically, I recommend women who are high in Openness to Experience. She will be more open-minded and interested in your views of the world, and if you are also high in Openness, you will be more interested in hers, and you both will be more understanding of the other in the event of disagreement.

Female rationalists may well be great matches for male rationalists. But they are rarer, and they don't hold a monopoly as good matches for a male rationalist. Consequently, a male rationalist is best off dating a variety of women until he discovers through actual experience what types of women he is best matched with.