Ok. For those who are interested. After what I have read in the Internet I got the following information.
Newer version of Crosswalk makes your APK heavier since it's simply bigger application cause of new features/patches. However newer Crosswalk versions have fixes which make your app work properly on more type of devices. Also it should improve performance of your game especially on older devices.
So that's what I found out. If there is anyone who can confirm that or deny, it would be nice if he/she would share his/her knowledge.