Upgrade my integrated or use it as a pre?

Hello all. I was hoping for some insight. I have some money saved up which I'm thinking of putting into my system, specifically an amplifier. I currently have a Classe Cap-80 integrated (100W) which I am generally very happy with. I've been toying with the idea of adding a power amp (used Classe Ca100 or Belles 150A hotrod) and using my integrated as the preamp. If I were to go this route would I hear a substantial difference or would my integrated/preamp be a limiting factor. Should I just save for a better integrated? (Plinius, YBA?) Actually something like a used Plinius 8100 is within my budget. My main issue with my current set up is that while it sounds very good on small scale stuff it has difficulty with large scale orchestral music (loss of transparency, congestion) and I've been told that using seperate amp/pre would help in this department. Any thoughts on this? The rest of my setup is a Meridian 506.24, Tyler Acoustic Taylo Ref. monitors, Acoustic Zen cabling. The room is small/medium (23x14x9) so i don't think I would need more than 100W. Many thanks in advance.
I would either save up for a better integrated or sell your current one, get a used amp like the Belles for around $850 and then get an inexpensive pre, probably passive. Then save up for a better pre. The rest of your system is very nice and is probably thinking "Get me a better amp". (not that the Classe isn't nice)

You could upgrade the amp for now, use the intergrated as a pre and buy a nice pre when you have the coin. Just my 2.
Thanks Matty and Cosmic. I think I will go for a power amp now and then save up for a better pre later when the funds allow it. I guess my question was more about whether i would hear a significant improvement after adding just the power amp to my integrated. I'm sure with quality pre AND power it will be obvious.
I used to have a Krell 300iL(intergrated). I ran an Audio research preamp through the unit and got great results. It sounded much better than the Krell's pre section.
Depending on how far up the foodchain you go on a new amp I don't think that the difference might necessarily be a slap you in the face kind of difference. Many changes in audio are subtle like extended frequency response, more airy highs, warm mids, firm bass, etc.

My suggestion would be to take your intergrated to your audio dealer and audition it with the amp you are considering purchasing. That would give you a fair idea of the difference between new amp/ old amp.