Thank you , all .
I read all your suggestions & tried everything to conclude that
(1)qiv , flpicsee is like xzgv if single file argument is passed which is usually the case in window managers (based on freedesktop.org) .
Eg:- I have pcmanfm file manager . There is ~/.local/share/applications/userapp-xzgv.desktop which has 'exec=xzgv %f' inside it , alongwith mimeapps.list pointing to relevant .desktop file. So cannot browse through all pictures in current folder easily. Passing * as argument is not specific because I wanted picture viewer to open file i have double clicked & previous/next to see others.
(2)gqviews with middle click & left click for next/previous is alright.
(3)eog is okay too.
(4)gpicview is lightweight yet all I need . My choice .
(6)Regarding gthumb I was going to post
gthumb: error while loading shared libraries: libexiv2.so.6: cannot open shared object file: No such file or directory
I will try that fix.
As told above I am using pcmanfm with support for multiple tabs unlike rox.