We are buying a new house next year - selling the big monster we live in now since we will be down to 2 kids (from 4 currently). Either going to build from scratch or buy and add a trophy room. Current hose has animals scattered everywhere.

I was thinking a 30x50 room with 14-16 ft ceilings. Room for 50+ trophies currently, including 4 pedastals, a few large life size mounts, and an elephant skull. want room to add another 50-60 trophies over time.

Is 30x50 big enough?

Or regardless of size, is there a good ratio of length, width, and height?

Regardless of the size you end up picking make sure you use 3/4 inch plywood behind the drywall. It makes mounting your trophies much easier.

1,500sq ft. Is pretty good sized space comparatively speaking. Like 1/2 slam said, its trophy room 101 to put plywood behind the drywall.
Ceiling height is paramount as many large animals really soak up wall space! I went too small some years ago. When you start adding up animals like Kudu, Gemsbuck, eland, elk, moose, lifesize Leaopards or Sheep...etc..etc... It adds up fast.
Also, do you need to plan for extra space for say a nice bar, or theatre/tv/sports place?
A friend of mine has a room with those basic dimensions and his architect drew up a recessed stage on one side about two feet up... It really made a great area to present the animals and it raised them up a bit. He has a Lion attacking a Sable there and several pedestals etc.
Point being is there is no such thing as too much space and go as big and as high/tall as you can afford to.

My friend placed 2-by wood around his room at various heights. I like the 3/4" Plywood the best with studs located for the really heavy stuff.

On ceiling height, I think about 12 is as high as I'd want to go or at least as a "no higher line". If you get the trophies to far up, you can't enjoy them.

On a 12' ceiling you can easily place 3 deer size game vertical, 2 mid sized game, or one large animal. The question would be if whether you would ever want to go higher than that and still see the trophies?

I would do a minimum of 14' ceilings, and would seriously consider 18-20'. Moose, elk, stags, elephants, all need major space...

If you look at the picture in my post "need help on 30 x 30 trophy room", that room, if I remember correctly is 24 ft wide, 9 1/2 foot walls and a 7 or 8/12 pitch. Inside ceiling height is about 18 feet.

You will also need to consider the type ceiling (cathedral,etc.) And the type of trusses to be used. Pick the wrong truss and you can lose some major space. Here's a site to give you some idea on ridge beam height. http://www.pole-barn.info/roof-pitch.html

I like the vaulted ceilings. I think a 14'-16' height would be good. I need to look at my buddy's trophy room again - I think his is about perfect.

Here is a ceiling design I found that I like (obviously the scale is different and the room is not a trophy room, but like the angle and finish).

Ceiling height isn't nearly as important as wall height. Over and over again I see tall, open ceilings with 8 ft walls and barely any room to put animals on the two longest walls in the room. I have 12 ft walls in my shop that I'm currently keeping my animals and I think that's just right. I can get two rows of mounts on there without crowding them, and even more with smaller heads.

I would defintitely go no lower than 12' wall heights. That what I have in my house now. I may go to 14'. I'm afraid 16-18 is to much.

My walls are 13 feet and there isn't a single animal that is too high. If I had it to do over again, I'd go 14'.

Something I've never seen used that I think would look real good and give a whole lot more "wall space" for heads. IS a drop wall along the ridge beam, say drop the bottom of it down to the same height of the outter walls and run it as far as you feel looks good. It could be cut back, or lengthened real easy later too.

OT: I built a drop storage lumber rack in Dad's garage when he bought a whole bundle of 24' 2x4's and had no place to put them. "Just got 'em because they were too cheap to pass up," Same with a whole bundle of 3/4" particle board. That's a bunch of space takers. Not sure now how high his garage walls were but, I talked him into going two blocks higher than normal and it worked and looked great. The door was 24' wide and I believe 10' high, if not, it was for sure 9' high. Very handy! Bldg was 30'x34' it seems. He's gone and the place has been sold.

One thing I fully believe in is: you can't make a trophy room, garage or workshop too big. Lowe's, H/D, or W/M super store might not be big enough for some of us!

Just some random thoughts this time.
George