Not so much more bottom, but rather a different low-end distribution. You've got a big peak going on with the bass around 200 Hz that's making the low end sound muddy. 
 
Use an EQ with a good spectrum display or use SPAN in conjunction with any EQ and you'll likely see the problem. Take a look at the overall slope of the recording. If you're using SPAN you can determine the mix's slope by clicking the Edit button and turning the Slope knob until the display is more-or-less horizontal. The number below the Slope knob will be your overall slope. For reggae you probably want something between 3 and 4; my ears are saying this mix is more like 5 or 6.
 
It could also benefit, I suspect, from a little more upper-midrange content in the 2-3K range. If you've got any plugins with a harmonic exciter such as Ozone or Alloy, you could probably beef that range up using an exciter band rather than EQ boosts.
 
If you want a musical suggestion, IMO no reggae piece is complete without a bubbly Hammond. A tambourine would also be beneficial. Just my own uneducated expectation, based on listening to Marley for so many years.

This is really appreciated Dave, Thanks.

Hi. I thought is was groovy and laid back. This kind of song does not (in my mind) need to be "pumped up".
All the best.

really good work  nice laid back groove
 
I don't like all of the vocal processing you've done, I'd take a lot of that off and take it easy on the verb
 
good stuff!

GREAT tune, GREAT vocals, Perfectly mixed! Definitely sounds like something I might hear Eric Clapton covering someday. I personally don't feel like the vocals are over-processed. You have a great voice and this song displays it well.
All that said, it feels like the song runs completely out of steam in the chorus. There's a "something" that should be in there, but what? Maybe a nice little piano or electric guitar counterpoint in the background? Something ...

Well now, that was a fun listen.
 
Great little tune.

+1 to the above - nice song!   Nothing to add to the mix comments at this point.    Arrangement-wise, other than some organ as bit suggested perhaps more of a "group" vocal in the chorus?   Picture 3-4 singers, stage right...