OK, there's one or two things I don't get in your overview.
Are you doing voice interviews with the Church Cards??? Why? Or is your question about taping gigs?
Using optical in on the H1xx + external AD, your noisefloor will be better than the PMD620, which lacks digi-in.
Regarding built-in pre, I'd say that the Iriver is not sufficient if you run analog in. You can add +20dB or so in the analog range, but if you do voice interviews, that's not enough by far. I don't know if the 620 is any better in that aspect.
Comparing the Church Combo>H1xx vs PMD620 with internal mics, I'd say that the Church gear wins, in a concert situation.
For an interview, comparing mountable external mics with a handheld all-in-one, I get the impression that mic placement can make or break your recording, and is far more important than the recorder. So you should reflect on your experience on how you usually mount the mics and whether that gives you good sound or not...
I'm using the Church CA-11 cards for both musical recordings (traditional folk instrument bands in China) and for speech recordings during interviews.
I must use cardiods for voice interviews because surrounding noise is very high- using omnis records too much background noise.
Now I'm thinking I might just use the iRiver H140, Marantz 620, and an Olympus LS-10 using CA-11 mics through the mic-in ports and NOT use a preamp.
This will simplify my setup -- I can avoid using pre-amps and avoid the possibility of wires coming disconnected.
BUT, you mentioned that the H140 preamp does not provide enough gain. So will I be better off using a Church preamp?
I have a STC9000 now that provides an extra 30db gain. Should I get another for my other gear? Or should I get the STC9100 which can only provide an extra 20db gain? (what makes the 9100 better than the 9000?
Regarding the Church pre, I think The Man himself is best suited to clarify the difference. Paging Chris... But make a search in the Retail section, IIRC he did outline the different spec in a posting there.
So your current gear looks perfectly good to me!
For music, I would run CA11>STC9000>PMD620 (or H140, the results should be similar)
If the music is loud and you want a lighter rig, try leaving out the pre and run CA11>PMD620, and check if the gain is sufficient.
For voice, I'd run the same rig, but I'd think twice about the mics.
If I had money to burn, I'd invest them in a proper "interview mic" instead, that can be stand-mounted or handheld, maybe even with a shotgun cap. That way you can direct it towards the interviewee and eliminate even more noise. Since it's not a stealth situation, why restrict yourself to miniature mics?!
As the saying goes: put your money in front, ie the mics!