Hi Sambini,
We're at a similar stage.
I'm into my 7th build (all small-ish projects) and have discovered that PVA
isn't the really the one for large paper pieces. It contains water which warps the paper of course and hardens by evaporation of the water.
You'll see for yourself but I got 'dimples' 'ripples' whatever the term or expression.
Have you seen this post by Rick:
http://www.papermodelers.com/forum/457266-post2.html
Heres the result I got yesterday glueing the keel of JSC's 'BUTE'...