Admittedly, I have not seen GB:FE, but the trailer looked like it had some neat visuals.
The worry of too few ghosts/monsters does not really concern me as each house usually only has 10-ish scenes. That and, honestly, Monstruos is advertising four monsters to fill out its house, so when people say there are only four-ish ghosts in GB:FE, it really does not seem all that different to me.
And, finally, the original GB movie was one of my bucket list houses, but I was not a huge fan of the previous GB house. It mostly came down to me feeling it had pacing issues or some strangely constructed scare tactics. Therefore, I do not really care which movie they use, as long as they give me some good sets along with striking a good balance between flow and scare tactics.