Upgrade cartridge or turntable?

Get a new stylus and save more money. Let us know when you get to $5000.

I'd throw a Dynavector 20 XL or whatever suits your budget on the table - the Planar 4 can definitely handle a big cartridge upgrade no problem.

According to expert advice I ignored in my youth, turntable first, tonearm second, cartridge third. I ignored this advice, to my cost. For one thing, turntables and tonearms don't wear out.

Another thing to consider is bang for buck. There is a tonearm which is within your budget which punches far above its weight (and cost): the Trans-Fi Terminator (yeah,  I know, but I didn't name it). Air bearing sled, and solid, intuitive, repeatable adjustments just like tonearms costing 10 or 20 times as much. I have two of them, running MC cartridges with an air bearing TT.

Put the balance into a record cleaning machine - I like ultra-sound. Works for me, but YMMV.

Get a new stylus and save more money. Let us know when you get to $5000.

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According to expert advice I ignored in my youth, turntable first, tonearm second, cartridge third. I ignored this advice, to my cost. For one thing, turntables and tonearms don't wear out.

Mike and Terry are right. The challenge is making the leap to buying turntable/arm/cartridge separately, when the combination you might ultimately want adds up to $10k or more. 

The tried and true approach is to find the very best table you can afford, and run it with a budget arm and cartridge, until you can afford to upgrade to a really good arm, and then finally cartridge. 

This way you spend the big money on things that really just do not wear out, so they are keepers and nothing is lost in the resale/upgrade treadmill. 

Another beauty of doing it this way, its almost impossible to find a turntable or arm that expensive that's not really, really good. VPI and Rega can sell based on ads. Nobody bought an Origin Live or Graham arm based on an ad. Their "advertising" is word of mouth. 

Take your time. There's a lot more going on than just sound. Another big factor with turntables is the way they look, feel, and function. Pay attention to all those details, plan out your path, take your time.

Miller is dead right about the look and feel. I use top line vintage test equipment like oscilloscopes and signal generators just because they look and feel better. It makes a big difference when you look forward to fiddling with things, rather than just enduring the necessity of doing so.

And, as Miller also says, "...take your time."