Yes, you can remove the default lockscreen
The default loackscreen you talk about is none other than the keyguard of the navi launcher. Yes, I do agree that it is quite a bit irritating to always swipe up every time you unlock your screen.
To remove this, the fix is simple:
1. You need to first root your device.
2. Open build.prop from /system [Use Root explorer app from the play store]
3. Search for navi keyguard support in the following lines, and change that particular value from 1 to 0.
You will now have Android's default lockscreen on your e7. Cheers.
Oh, and if you want to take it a step further and delete the keyguard, you can do so, with Titanium Backup.