With regards to why Ryanair want WW, The only reason comes to mind is that FR are stuggling to get Captains, no sooner do FO's reach command level they are promoted. And with taking on WW flight crew have the ability to fly 738 without much more trainning required. With regards to cabin crew, Ryanair have a high turnover in crew each year im sure having a further 450 (already based) wouldnt be much hassle to them.
However all a theory.. Waiting game ;-)