Except that he doesn't own the preamp yet, and he's only guessing that it won't have enough gain. It very well might have enough gain. He is assuming he will have a problem he doesn't even have yet.
If the Brick doesn't have enough gain, the way I would do it is get as much gain out the Brick as possible and then tweak it up a little after the Brick if necessary.
There would not need to be a line level input on the preamp. And if there were, you would *not* use it. The reason being that a line level input on a preamp would probably be a DI input, which would just knock the signal back down to mic level. The opposite of what you need to do if you are amplifying the signal further.
All you'll need from that second preamp is a very little more gain. Not much at all, if at all. Get the Brick first and see if it does it for you, then look into a second preamp only if it becomes necessary at that point.