What should I upgrade?

tl;dr Looking for ~$500 suggestions for upgrades, used parts OK

Looking to upgrade my 2014 gaming rig. It's served me well until recently mainly due to a transition from r/patiengamers to Helldivers2 and BG3. It's struggling, getting 20fps at best on low-mid settings. I presume I need a significantly newer GPU based on GPU usage but not sure what's an appropriate jump without being signifcantly bottlenecked by other parts of my build.

MY 2014/Current Build:

PCPartPicker Part List

Type Item Price
CPU *Intel Core i5-4690K 3.5 GHz Quad-Core Processor $53.00 @ Amazon
CPU Cooler Thermalright TRUE Spirit 140 POWER 73.6 CFM CPU Cooler -
Motherboard Gigabyte GA-Z97X-UD3H-BK ATX LGA1150 Motherboard -
Memory G.Skill Sniper 16 GB (2 x 8 GB) DDR3-1866 CL9 Memory $199.00 @ Amazon
Storage PNY XLR8 CS2311 250 GB 2.5" Solid State Drive -
Storage Samsung 860 Evo 1 TB 2.5" Solid State Drive $149.99 @ Amazon
Storage Seagate BarraCuda 1 TB 3.5" 7200 RPM Internal Hard Drive $27.00 @ Amazon
Video Card Sapphire Tri-X Radeon R9 290 4 GB Video Card -
Case Corsair Vengeance C70 ATX Mid Tower Case -
Power Supply Antec High Current Gamer 620 W 80+ Bronze Certified Semi-modular ATX Power Supply $155.31 @ Amazon
Wireless Network Adapter Ubit G10H-AX210S 802.11a/b/g/n/ac/ax PCIe x1 Wi-Fi Adapter -
Case Fan ARCTIC F14 77.3 CFM 140 mm Fan -
Case Fan ARCTIC F14 77.3 CFM 140 mm Fan -
Monitor Dell AW3821DW 37.5" 3840 x 1600 144 Hz Curved Monitor $899.00 @ Amazon
Keyboard Keychron K6 Aluminum Frame RGB Wired/Bluetooth Standard Keyboard -
Mouse Razer DeathAdder Wired Optical Mouse -
Headphones Audio-Technica ATH-M50x Headphones $148.25 @ Amazon
Prices include shipping, taxes, rebates, and discounts
Total $1631.55
*Lowest price parts chosen from parametric criteria
Generated by PCPartPicker 2024-04-06 14:35 EDT-0400

Note: GPU BIOS flashed from 290 --> 290x. OC at GPU Clock: 1105MHz, Memory: 1600 MHz, Voltage: +0.4 mV

Note: CPU OC 4.0GHz