Well, I've something that works good enough for me now

• With a CP2102 (3.3v) just 1 1N4148 for D5 seems to work (removing D1 and D2). For safety I put a 470 ohm in series with D5. This is using the CH_PD diagram.
• Uploading works like this with stock Arduino (Actually I have it set on NodeMcu mode).
• But serial monitor messes it up, so instead I use non stock Arduino IDE from: https://github.com/esp8266/Arduino/issues/316 it disables serial monitor messing with DTR/RTS :).

Hi! this is cool
Some questions:
I'm using a similar design with a CP2102 which only has DTR, and operates at 3.3V.

• You say that in this case D1 and D2 can be removed, I assume these are the same in the first and second diagram? (they are not numbered in the second diagram ).
• Is the reason to use Schottky (only) the low forward voltage? I only have some 1N4148, using one for D5 seems to work, using it for D1 and D5 does not for some reason
• The B5819W would be the same as 1N5819 I assume? Might order some, do you think it's a good common Schottky to have?
• How do you make this work in software??? Setting DTR on, then off, does put it in flash mode, and Arduino software in NodeMCU mode does manage to flash correctly. But Arduino Serial monitor seems to set the DTR wrong, then it stays stuck in flash mode