One of the reasons I like this site is because there is no screening. I like to think I can produce photos of reasonable quality. I have submitted to many sites and had fairly good success, but another site I submitted to in the past became increasingly difficult to satisfy.
For example, the resized photo in the MS-Paint instructions would be unacceptable because there is too much dead space around the aircraft. A tighter crop is required. Preferably a 16 aspect ratio rather than the standard 4 ratio, as shown in the image below, to cut out the excessive foreground and sky. Secondly, there is vignetting in the top corners, ie. darker shading than the rest of the sky. And thirdly, the white cowl on the nose is over-exposed, and yet excessive Photoshopping is not acceptable either. It all makes for a very low acceptance rate.
It's funny, but camera clubs dislike centered images, for the the 'rule of thirds' applies, where you divide the frame in three, horizontally and vertically, and then place the subject on one of the intersections of those lines.