Just an Addendum of useful information from me:
If you're using a Nvidia GPU made in the last 4+ years on a laptop (EVEN A LAPTOP VERSION OF THE RTX MODELS), you owe it to yourself to look in the control panel and tweak stuff, both for games in general and for City of Heroes specifically.
All laptops: Power Settings - Nvidia Controlled. This is absolutely essential for reducing heat and power consumption while increasing framerate. I don't know how it works, but it's made my game more stable, less worrysome to multitask with, and allowed it to produce less heat, all while cranking up graphics a bit more. I recommend setting this universally, as almost all games use an API it works with. Presumably it reduces visual quality of stuff that the player isn't likely to notice as much, intelligently. (Source: Here )
Anything in the 1070/1080 or 2070/2080 models: 16x Anisotropic Filtering forced int he GPU control panel. A few Anisotropy tweaks at High Performance/Performance/Quality to slightly reduce overhead on texture filtering. If you're using newer drivers, a 30 or 60 FPS framerate cap depending on what you can handle at current settings (Further reduces GPU use and thus heat, which improves stability and prevents performance degradation), and if your drivers are especially recent, there's a built in full screen sharpening option that works on all OpenGL, Vulkan, or DirectX renderers for improved visual quality (I recommend 50% screen sharpening with 100% "Ignore film grain" to soften it a bit, and FXAA enabled to further soften the image so that the added detail looks like it was always in the game).
Debatable but probably harmless: Most games released before Unreal Engine 3 that use OpenGL supposedly benefit in terms of microstutter reduction from turning "threaded optimization" to "off". Results online have been mixed, but in my observation it makes little to no difference but also causes no harm and no visual glitches to speak of. This is a surface level setting in the control panel so I'd wager its harmless to have it set wrong anyway. Additionally, because I discovered that City of Heroes was shut down before CUDA processing became commonplace (and in fact, used a pre-CUDA PhysX setup that required a specific type of card from Agaia to hardware accelerate physics processing) I recommend disabling CUDA processing entirely in City of Heroes profile.
Similar tricks for AMD cards may exist, but might also require special tools (My understanding is that they don't have game specific profiles in AMD's control panel yet)
As a note, my current laptop has a Nvidia RTX 2070, an intel core i7 8th Gen, 16 gigs of RAM (Upgradable to 32 or 64? Can't remember which of those it was), and a 500 GB solid state drive. I run the game off of a 2 TB USB 3.0 connected HDD, with no issue except that game music sometimes stalls independant of framerate for a bit (A problem unique to this game when running from that drive!).