  We identify a set of planetary systems observed by \textit{Kepler} that merit
transit timing variation (TTV) analysis given the orbital periods of transiting
planets, the uncertainties for their transit times and the number of transits
observed during the \textit{Kepler} mission. We confirm the planetary nature of
4 KOIs within multicandidate systems. We forward model each of the planetary
systems identified to determine which systems are likely to yield mass
constraints that may be significantly improved upon with follow-up transit
observations. We find projected TTVs diverge by more than 90 minutes after 6000
days in 27 systems, including 22 planets with orbital periods exceeding 25
days. Such targets would benefit the most from additional transit timing data.
TTV follow-up could push exoplanet characterization to lower masses, at greater
orbital periods and at cooler equilibrium temperatures than is currently
possible from the \textit{Kepler} dataset alone. Combining TTVs and recently
revised stellar parameters, we characterize an ensemble of homogeneously
selected planets and identify planets in the \textit{Kepler} field with large
enough estimated transmission annuli for atmospheric characterization with
JWST.
