PC Master Race

Two observations:

1. Your fan layout in your case is not optimal.
2. Your GPU idle is high, but not dangerous.

Fan layout in a PC is very straightforward - cold air in, hot air out. You want the airflow to be constantly moving and not choking. So first off, good on you for trying to balance the count of intake fans vs count of exhaust fans. I noticed in your observations that you're wondering if your exhaust fan is detrimental - you are correct. The problem is that you are exhausting cold air before it even reaches your PC components. A common problem I see with inexperienced builders is that they try to fill as many slots as they can with fans. More fans doesn't equal more cooling. Remove the top exhaust fan that is closest to the front intake (i.e., the top right exhaust fan as it is exhausting cold air). For your last top exhaust fan, move it as far left as you can (so it sits in the top left corner of your case, basically behind your CPU cooler). With this adjustment, cold air goes in and actually gets to reach your CPU cooler, and then all the hot waste air is optimally pulled out of the top left corner of your case (via both the rear case fan and the top exhaust fan).

For your GPU, based on reviewing your comments in this post, I assume you're probably an inexperienced/new PC gamer. And that's totally fine of course. Thermal Junction temperature of a GPU is generally certified by the manufacturer to reach 100-110 C. This of course is entirely dependent on the manufacturer, so check your GPU make/model, go to their web site, and look at the certified operating temperatures. Ideally, keep the hottest point of the card much colder than that. If your GPU is idling at 58, start by increasing your fan curves for your GPU. In general, you want more fan speed for higher load. Do your best to try to target ~70-75 F when doing heavy gaming (gpu temp 70-75 F, Tjunction and mem < 90 F) depending on the games you play.

My recommendations:

• Inspect your GPU for wear/issues.
• Clean your PC from dust. Blow canned air (or get a computer duster) through the GPU fans and heatsink and try to get rid of as much dust as possible. If you use a computer duster, make sure to hold the fans still as you blow through them, or else you can make them spin faster than the bearings can handle, which will damage the fans.
• Set a proper GPU fan curve to balance noise and cooling.
• It's okay for your card to get hot as these cards can go up to 100 F, but it is ideal for longevity to keep it much cooler
• Optimise your case fans to have curves. Ideally, bind the case fans to the GPU so that when the GPU ramps up, the case fans ramp up too. If for any reason you can't bind your case fans to the GPU, instead whenever you play an intensive game, just manually increase the fan speed to something like 1200 rpm just to bring more air in). Ideally for noise and airflow when doing general computing, your case fans don't need to spin fast at all - I keep mine around 700 rpm.
• Balance your case fan speeds to match 1:1. In my above recommendation, you eliminate one exhaust fan so you are left with 2 exhaust and 3 intake. That's okay. The ideal for case airflow is neutral air pressure (the same amount of air brought in will leave the case at the same rate), but the alternative less-ideal situation is positive air pressure (air comes in faster than you can exhaust it). However, be careful when balancing positive airpressure airflow. If you have way too much air coming in (e.g., 2000 rpm intake fans running at 100%) vs being exhausted (e.g., exhausting at 20% fan speed), you end up hurting airflow. What happens is you ram too much into the computer, and it has nowhere to go because the exhaust fans can't keep up with how much is coming in. Eventually, the hot waste air from your PC components ends up getting mixed in with the cool air over time, and you end up with a hot box. Eliminate this problem by having the exhaust fans run at the same speed as your intake fans - always.
• And finally, make sure you have an airflow-friendly case. I don't know what case you're using, but as long as it's not a bad case with filters or obstructions that choke airflow, you should be good. I've been using a Corsair 5000d airflow for several years now, but there are much newer cases that are better for airflow.

When you become more advanced:

• Do not do this part until you have experience and know-how!
• Disassemble your GPU, repaste it, and consider replacing the thermal pads if they're worn.