Question How to keep system cooler after new GPU. Extra fans?

[NightHawkRMX]

Hello, I just added an RX480 to my system and I love the way it performs. I also love the way my system looks now, so I put it up on my desk. It used to sit on the floor next to my desk, which resulted in a ton of dust getting in it 🙁
System Specs: https://pcpartpicker.com/list/HwFZhy

https://imgur.com/sHHZZx0

View: https://imgur.com/sHHZZx0

https://imgur.com/a/poEmpbt

View: https://imgur.com/a/poEmpbt

I am currently using the stock top intake and rear exhaust fan. My PSU exhausts out to the bottom.
Under load, my GPU gets to 78c and I can feel a ton of heat coming from the front of the case where there are no fans. My 480 isnt overclocked and is dust free. I think the thermal paste may be dried up.
I feel a lot of heat from the rear of the case as well.

Should I also buy 2 really cheap case fans and mount them at the front for extra airflow. My motherboard has enough fan headers for 4 fans.
Also, I was considering getting LED fans rather than standard fans. I was thinking of red or white fans. Which do you think will look the best in my case? I may move the stock fans to the front so I can see the led ones in the rear.

 

[NightHawkRMX]

Fans came. Will install them now.

 

[NightHawkRMX]

Update:
Just installed the new Arctic fans into my system. Also realized the top of my case can take a 140mm as well, but I'm just using a 120mm for now.
Fan setup:
1x AMD Wraith Stealth
2x Arctic F14 PWM 140mm: Front Intake
1x Arctic F12 PWM 120mm: Rear Exhaust
1x Arctic F12 PWM 120mm: Top Exhaust
All system fans are set to run as PWM and set to run in smart fan mode. If I set max speed, case fans will go to about 1500rpm in bios, however, this is loud and unnecessary.

New fans are a little louder, to be expected. Not terribly loud.
Oddly enough, 3 of the 4 fans came with black wires and plug. The 4th came with colorful wires and a white plug, even though that fan was bought from the same seller as the other 120mm.

Just stressed the GPU for a while in games. Most of the time my temps were around 70c and the highest I saw was in the mid-70s, which is pretty good. I saw temps in the 80s before. I am looking to overclock a little, so do you think I have enough thermal headroom to overclock my GPU? Do you think a repaste would help as well?