One way to simplify the combinatorial problem in SMIRKY or future packages for sampling chemical perception trees would be creating a more efficient move set. As discussed in Section 3.2.2, SMIRKY currently considers all possible decorators for the atoms and bonds, whether or not they make chemical sense, and thus wastes considerable time proposing patterns that do not match any molecules. Considering the low probability of picking a given decorator, the fact that SMIRKY is able to find SMIRKS patterns which match 120 (88%) of the reference torsions is further evidence that we have been fairly successful in sampling the chemical perception tree effectively. However, if we could increase the probability of picking good decorators, we could decrease the number of moves required to sample the requisite chemistry. Future progress of these tools should leverage moves which only employ chemically reasonable combinations of decorators. For example, a double bond decorator should never be allowed next to a tetrahedral carbon which only has single bonds. This information would not necessarily need to be provided by a human expert; instead, molecule sets used for training could be used to extract this information.