@Marco-G gpu_mem=320 is pretty much essential if you want to play high bitrate 4k hevc. You don't need as much if you don't play this kind of media.
About hdmi_ignore_cec_init=1, what it does is to not switch (the TV) to the Raspberry Pi/Retropie source when it is started or rebooted. It has no effect in anything else.
Please do not post a support request without first reading and following the advice in https://retropie.org.uk/forum/topic/3/read-this-first