Future experiments that could be done would be to: replicate the experiment, fully cross all combination of mutants and genotype the yeast colonies. The first experiment that could be done is to replicate the experiment. By replicating the experiment, the results would be more certain. Another experiment that could be done is to cross mutants with the same mating type. By doing this, the genotype of the mutants can be better determined. For example, if unknown a 1 was crossed with it self, and the resulting diploid colony grew well on YED and MV+adenine plate but poorly on MV plate, it can be determined that, the mutation is still in the adenine pathway. Yet another experiment that can be done to confirm the site of mutation is to genotype the colonies. By extracting the DNA, and sequencing the DNA, the exact nature of the mutation, whether it is a spot mutation or a missense mutation can be determined. By doing these additional experiments both phenotypic and genotypic traits of the mutant strains can be determined.
Comments
improvising
Instead of replicating the experiment, think about specific methods you could change. What would happen if you exposed the yeast to UB light for a longer period of time?
Redundancy
There is some redundancy. For example, at the start of the paragraph you state three times that replicating the experiment would make for a good future experiment, this seems unnecessary.
Awkward Sentence
I found some small issues in spelling/wording in the sentence, "if unknown a 1 was crossed with it self". You likely meant "itself" and i'm guessing "a 1" was a genotype which you might want to mention for clarity.