I responded on shmups, but I’ll reiterate here:
0. You’re not using component from the NES, you’re using composite. The only way you’d be using component is if you had a NESRGB already installed, along with the component video addon board.
2. It’s a basic solution. You can turn off the line doubling on the RT2X to use the OSSC’s line-doubling, but you still need an HDMI to YPbPr converter to use it with the OSSC.
3. Koryuu is different, not necessarily better, than the RT2X; but it arguably pairs better with the OSSC than the RT2X, because it gets you from composite and S-Video to component in one device rather than two. The Koryuu is not a scaler, so it will only output at the same resolution as it’s fed; and, since it’s limited to 15kHz inputs, you’re not going to get anything out of it other than 240p/288p/480i/576i/PAL60.
4. The OSSC doesn’t have filters, just scanline and border fill options. The main point of the HDMI mod is to get you a nice, crisp, clean image that will be compatible on pretty much any HDMI TV. It’s been a while since I’ve looked into it, and while I’m pretty sure the HDMI mod also has scanline options, I’m not sure either product is going to get you something that really looks like a CRT.