PC Upgrade - upgrade parts or build new system?

[Santander]

I built my current computer back in 2009 or 2010 and upgraded a few things along the way. I'm now debating whether I should just build a new SSF system for around US$1k that I can use for another 5-6 years or just upgrade the RAM and HDD and delay the upgrade until I really need it. I don't play games much, and the only modern game I have is XCOM2, which this computer is (barely) capable of running, but I'd welcome better performance. I conduct some data analysis at home sometimes, but I usually leave the heavy lifting for the workstation computer at work. Again, I wouldn't mind having some more horsepower to conduct some other projects. Other than that, my computer usage is pretty basic. My system specs are below. What would be money better spent - $200 or so to buy 8GB of RAM and a SSD, or $1k on a new machine? Thanks!

PCPartPicker part list / Price breakdown by merchant

CPU: Intel Core i5-750 2.66GHz Quad-Core Processor (Purchased For $0.00)
Motherboard: Gigabyte GA-P55-UD3R ATX LGA1156 Motherboard (Purchased For $0.00)
Memory: Mushkin Blackline 4GB (2 x 2GB) DDR3-1600 Memory (Purchased For $0.00)
Storage: Seagate Barracuda 500GB 3.5" 7200RPM Internal Hard Drive (Purchased For $0.00)
Video Card: XFX Radeon HD 7850 2GB Core Edition Video Card (Purchased For $0.00)
Power Supply: Inwin 550W 80+ Bronze Certified ATX Power Supply (Purchased For $0.00)
Optical Drive: Samsung SH-S223Q DVD/CD Writer (Purchased For $0.00)
Operating System: Microsoft Windows 10 Home OEM 64-bit (Purchased For $0.00)
Wireless Network Adapter: Linksys WMP600N PCI 802.11a/b/g/n Wi-Fi Adapter (Purchased For $0.00)
Total: $0.00
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2017-01-07 18:41 EST-0500

PCPartPicker part list / Price breakdown by merchant

 

[Herc08]

Well RAM and a new hard drive would give a bump in performance, but not enough to justify it. If I were you, and have a grand to get a new PC, you can get a very powerful PC. You can get an unlocked i7, and a low end GPU since you don't game much. This build has the i7, but of course you can drop down to the i5 and save some money. Also gave your the RX 480, which should be able to handle any game. You could also get the GTX 1050 Ti and save $50-60, but I'm all about future proofing.

PCPartPicker part list / Price breakdown by merchant

CPU: Intel Core i7-6700K 4.0GHz Quad-Core Processor ($328.99 @ SuperBiiz)
CPU Cooler: CRYORIG H7 49.0 CFM CPU Cooler ($34.99 @ Newegg Marketplace)
Motherboard: Gigabyte GA-Z170-HD3 ATX LGA1151 Motherboard ($104.99 @ Amazon)
Memory: G.Skill Ripjaws V Series 16GB (2 x 8GB) DDR4-3000 Memory ($88.99 @ Newegg)
Storage: ADATA Ultimate SU800 256GB 2.5" Solid State Drive ($74.99 @ Newegg)
Storage: Western Digital Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive ($49.78 @ OutletPC)
Video Card: XFX Radeon RX 480 4GB RS Video Card ($204.99 @ Amazon)
Case: Deepcool TESSERACT SW ATX Mid Tower Case ($38.99 @ SuperBiiz)
Power Supply: EVGA SuperNOVA G2 550W 80+ Gold Certified Fully-Modular ATX Power Supply ($78.89 @ OutletPC)
Total: $1005.60
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2017-01-07 19:57 EST-0500