Being that you're quite literally new to this, I'll admit that for first time uploads, these aren't half bad!
Considering that I have a little bit of experience under my belt with designing liveries, I think there are a few things you should take note of when making liveries, or 'brands' as we call them here:
1. Color choice - a lot of designers on here like to use what are called 'color pallets', these are a selection of specific colors that, when put together, will compliment each other.
2. Font choice - Since you're a first timer, I'll let you off the hook with these. But for the future, consider using typefaces that are more simplistic and more importantly, accurate to the relative era of the specific airliner being painted. (I'll give you a little helping hand, most modern brands today utilize a 'Sans Serif' typeface )
I'll be eager to see future uploads of yours! And as an ending remark, welcome to AE!
-Vision