you are using only 1301 of 1472 pages. So, you can without any complications reduce the number of large pages from 1472 to 1301 and receive 171*16 MB free memory. PGA can’t use 16MB pages afaik. So this memory is only for SGA.
If you mean “user connection to Oracle” under “user’s process”, so i don’t know, how Oracle works in such details, but I presume (as I wrote), that large pages are used only for SGA. For all other purposes (such as PGA, LGWR, ARC0, user connections, and so on) Oracle uses normal 4KB or medium 64KB pages.