Finding the three pieces needed to make the first part of the first F2L block is a tough recognition.
This is indeed an important issue in ZZF2L, and something that you need to address if you're serious about ZZ. I've had quite a few comments from folks finding this an issue. I myself used to spend quite a bit of time looking at D and B .. you only need to ask Escher
I've since managed to stop myself from doing this, while still maintaining lookahead, but how?
Believe it or not, despite the hidden pieces, all the information you need is there, but you need to know what you're looking for to take advantage of it. If you don't believe me, then try doing a super slow ZZ solve. During EOLine, look for your first F2L pieces. Again, during F2L look for the next pieces while very slowly solving the current block. I guarantee that you will never fail to find something. If you do, then rewind back to the start of that block and try again. If you still don't see what you're looking for then message me with the case!
The reason you will see many ZZ solvers mess up lookahead from EOLine into F2L is really because they're unsure about their line plan and are looking for the line going into place, rather than looking for the next F2L pieces. It takes quite a bit of discipline to trust your EOLine plan and actively search for F2L pieces during EOLine exec.
Once you've built your first 1x2x2, there are a couple tricks which you need to keep in mind. Firstly (and quite importantly), you can often identify an edge using elimination. For example, if you've just solved the LH1x2x2, you're looking for the last LH edge. Well if UL is visible, then you can positively identify where your last LH edge is -
anywhere on the cube. I quite often find edges like this.
The other thing to realise is that when building a 1x2x2 block, it doesn't matter too much if you don't see all 3 pieces. Either of the two edges the corner joins to is sufficient to start building the block. The trick is to be flexible and accept either of the two edges as a starting point. The moves used to start the build will often show you where the final edge is (or isn't) before you're done.
Finally, I generally think that looking at B/D sides during the solve is a bad idea. It ruins your ability to look at other things happening around the cube and interrupts the flow. I think it's much better to do R/L turns to find what you're looking for, rather than rotations. They're faster to execute than rotations, and reveal quite a lot.
Wow! That was a bit of an essay, but you touched on an important ZZ F2L issue, which is a common concern for people new to the method. I hope this helps..