I would half the bonus if the PC would perform a minor memory technique: writing things down or repeating over and over again the piece of information (any easy quick ritual). Full bonus if the PC performs the extended time consuming rituals used by memory techniques. So +2 or +5 for Exceptional memory, and +5 to +10 for Enhanced Memory.
The skill check for memory depends on the technique - writing, drawing, area knowledge (for method of Loci), etc...
I should give Aging Memory Penalties at Adult (30 and older) and every level when remembering stuff not related to their profession. not a direct penalty to IQ
influenced by Professor Patrick N. Attill's the Art of Teaching and how we Learn by Professor Monisha Pasupathi