recommendation for a high end analog system


I never had an analog system until last month. I bought a 1989 SOTA TT with vacuum/Sumiko MMT arm/Dennon 103R retyped with elliptical/sapphire cantilever. My phono is Kitsune MK5 WBT that is amplified by Don Sach 2 tube preamp and Pass X350.5. My speaker are Sound Lab M545 ESL. The TT has been very   well maintained despite its age. It sounded very good until I heard my friend's system which has the same TT but with Lyra Skala cartridge and first generation Triplanar arm (Spectral pre/amp). His sounded noticeably clearer and fuller. What is the best way to get a noticeable improvement in my system without breaking the bank (or before I have to squint to hear the improvement). I would love to hear some wisdom from analog-philes.
128x128chungjh
@chakster 
I thought you'd like the Pickering - I ordered a replacement cartridge that I have yet to try by LP Gear - I'd have liked an NOS stereohydron - I will let you know how I get on
@lohanimal I was lucky to find NOS genuine Pickering D4000 stylus in the box :) 
Just read all posts and generally agree with most advice.  Must add my endorsement to “ditch the dust cover”.  It cannot improve and most likely will degrade the sound.  Next, I think you are expecting too much from your Denon 103.  I currently own a Denon 103m which is supposed to be the best of the 103 series.  My 103 has been retired with Andy Kim’s best.  I also own a Lyra Delos, a van den hul black beauty special X and an Air Tight PC-1.  The 103 is a “nice” cartridge but not in the same class as my others.  The Sota is an excellent tt and the Triplaner an outstanding arm.  I really think you would not be doing them justice with your Denon cartridge.
@vpi 

I am realizing that. I was hoping to get the "ultimate" sound on the cheap with retipped Denon 103R, but I guess you get what you pay for.