OK... here goes...
This one at least could work in today's market, not too Beatlesque or recognizably someone else's style...
Yes, WAY too fill happy. Record as a MIDI file and edit them to be different, paste in just some simple pickups instead of full fills if you want just a little lift (but better might be a pickup fill from the guitar or bass) in the middle of a verse or chorus.
The guitar part was too low in the mix (at times). It helps detract from the arranger nature of it, Bring it up.
My advice on the song would be to transpose up a step at about the halfway point. It needs a lift, and the song doesn't really provide it all by itself. Last verse and chorus might work better with a whole tone step up. It works on many songs. Give it a try...
Finally, I'm sorry to say it, but yes, even though it's a demo, you REALLY need to be a bit more picky about the vocal track. Pitch problems (which maybe ARE fixable with Autotune) but more especially, breathing and tone issues. You REALLY need to breathe better, and support that voice. Perhaps a couple of lessons with a good vocal coach might pay big dividends. And maybe some help with a good compressor to help even things out a bit. What are you currently using as a mike chain?
But, as another unrelated point (to this song, at least), one thing kind of worries me. You say you wrote this years ago. As were both the good ones from the previous batch. Trouble is, as a 'pro' songwriter, you are going to have to write LOTS of songs all the time. I know quite a few pro songwriters, staff writers for major labels, etc., and one thing they all are is prolific! They often write several songs a DAY
Out of several songs a day, maybe they would write one good one a week, and MAYBE one song a month would get picked up and retained. And maybe one or two songs a year would be a hit.
But they HAVE to write several a day to give them that shot at the hits. If you are still mining your back catalog, you might give a thought to what you will do when it runs out. Can you produce on that kind of scale? They don't have to be great songs. Often a great song comes out of something else you think doesn't stand a chance. But the more you throw at the wall, the more likely ONE is going to stick.
Just a thought...