Welcome back! I'm pleased to see your return... I always enjoyed your posts!
I recall your Trek-Formers contest, I had fun with that one... my entry was an Autobot whose alt-form was an old Constitution
I love your revamping of the BoP Starscream. I love the idea behind your Megatron, but I think he may be too stiff as drawn. He reminds me more of the (frankly terrible) original Megatron toy which was a beautifully convincing gun, but a pretty awkward looking robot. I do like his forehead details though...
Your freshened up starship designs are excellent. I'm equally reminded of Eaves' and Drexler's work when I look at them.. maybe even some of Sternbach's style from later in Voyager
. I almost want to suggest you try to clean up your line-work, but I kinda like the wobbly-ness of it... gives the drawing a sketchier, more energetic feel.
I love it!