Certainly the Gestation Times are all over the Place in the Franchise, does that IMPACT the Size? Who knows?
As the Protomorph had a Rabid Gestation and seem to be Larger than the Xenomorph Warriors. The Neomorph also had a Quick Gestation.
When it comes down to the Deacon it would appear this took DAYS.... i think we have to take into Account the Deacon we saw was from Dr Shaw's Fetus (Trilobite) which GREW Big Fast..... but this kind of Face Hugger is a HYBRID and has a LOT of Human DNA and maybe this Impacts the Gestation Time, or maybe when a Engineer is Infected the Gestation Time is SLOWER.
The Pred-Alien Procreation with the Direct Embryo Implantation was also a VERY FAST Gestation Period. I think what we have is that the GESTATION is just a PLOT Factor, and so each Movie the Producers/Directors come up with DIFFERENT Speeds to SUIT the PLOT/PACE of the Movie.
With the DRONE maybe it was the Way that Kane was taken Care of when he got back to the NOSTROMO and so in MED-BAY in some kind of Cryo-Assisted Rest/Capsule could account for the SLOWER Gestation?
You could Wonder if this is WHY we saw Sgt Lopes Gestation being Longer? Some could Argue that Orams was much Faster but we have to remember the MOVIE is NOT playing in Real Time.... When Lope gets Infected the £"$£% Hits the Fan and they Quickly attempt to make their Escape. The Time from when Lope meets up with Daniels and they make their RUN FOR IT to get to the Lander to when they get to the SHIP may be Longer Screen Time.. but David could have been ALONE with Oram for Hours.
It would have been Interesting to see Ridley Scott complete his NEXT FEW Movies and see HOW he would have Explored the Procreation of the Protomorph i would GUESS that he MAY have gone for the EGG-MORPH. I think the Egg Morph makes GREAT SENSE if THIS is How you can Create a Queen.
Finally talking about the QUEEN we did have ALIEN 3 and we saw that the Queen had taken a LONGER TIME to Gestate and so maybe XENOMORPHS that have the ability to Procreate/Reproduce are the ONES that take LONGER to Gestate?