I'm choosing 's' because it's among the most common consonants in English. Words ending in 'e' often start with 's' (like "simple", "secure", "sample"), and 's' frequently appears in many positions within words. Given that I've already found the final 'e' but none of my other guesses were successful, guessing a high-frequency consonant like 's' gives me a good chance of revealing more of the word pattern.