Paragon
This is a no brainer
Ask yourself this. What do you want to do as a career for the rest of your life. If its be a Commercial Pilot, then ask yourself this. When, not if, but when you lose your job because your company is no longer around, what and where are you going to go with a 145 rating. If you had a 320 rating, how would it be then ?
You need to move onto the 320. Guys came from your place to the middle east 2 years ago onto the 320 and are now returning to the UK for Virgin onto their 340s.
You can sit there with your command time building, but it means Jack **** when your out of a job. No one cares and you wont get another job no matter how many hours you have got on a 145 or how many hours you have got as command. No one cares. All that matters is how many hours on what aircraft and a 320 is 100 times better rating to have than a 145. Search for jobs and you will see.
PS, its not as bad as you think here