Looks like there was just resin on that deck with no glassfiber at all. The work you have done in the interior looks good, great start to a worthwhile project there! There is at least 1 member here who redid the whole boat except the transom, cause the transom was fine... then had to re-redo everything to fix the rotten transom, cost twice as much as doing it right first time... i thought my transom was fine, but once the stringers came out i found the rot - now im super relieved to have a solid trustworthy transom behind me! (and it wasn't that much extra work or cost). Good luck with it!