We have studied highly L10-ordered FePtAg-C nano-granular thin films as potential TAR media. These films were fabricated in a flexible sputter system allowing deposition of appropriate adhesion, heat sink and seed layers before growing FePtAg-C at elevated temperature to optimize grain size, distribution, texture and chemical L10 ordering. We obtained granular FePtAg-C films with well isolated grains, .e.g. of 7.4 nm +/- 1.4 nm, that show high coercivities Hc up to ~5 T and are suitable for TAR recording on glass substrates. Structural analysis suggests that the variation in anisotropy field is the largest contribution to the observed switching field distribution. In addition to optimized microstructure and magnetics, TAR media should include a suitable thermal design, underlining the need for thermal properties characterization. We will introduce our pump-probe technique as a sensitive metrology tool for thin films and multilayers. Anisotropy in the thermal conductivity due to grain microstructure in metallic films and size effects in nanoscale materials will be discussed.