Citadel Plaza

So i got bored and decided to build a citadel, so i looked around and found that in most cases a citadel was 2 things, a defensive structure as well as a symbol of power. so i decided to build my own. admittadely from the outside it is boreing but, it does have potential. so i'd like feed back any structural changes will be duely noted. however the plan from here is to create a rail service to my original spawn, build a market and Nether temple as well as some homes and adequate outer defences. im playing with the idea of pistons throwing up cobblestone as a gate, like the homes that are automaticall built useing pistons. im also going to try and create an early warning system that links all outer outposts to the citedal. but most of this is thought and currently experimenting. also when i started this there was no snow. at all. yet now i seem to be in the middle of winter so im presuming that i entered a snow biome and it didnt load properly when i first went there.

Update #1
OK so been a while, had a couple of other little projects since i started this main project, the nether temple (which kinda failed ((aim to fix this as soon as possible))) the gatehouse's which are actually reasonably difficult to build all looking alike, the Watch towers and walls, as well as the hidden piston (emergency wall)

the main changes from original post are the addition of these mini projects and the SEMI completion of the outer wall, just a small bit left now, my next projects will include a Elders forum and grand library,citadel market (anyone wanting to do a collaboration for the market I'm willing to send you my save) and either residential area (upper citadel??) and citadel gardens.

next update will most likely cover the wall, emergency wall, and elder forums.

Update#2
>Outer Wall has been completed and the watch tower project is at 50% completed
>Gate houses have been completed (SEE PICS)
>Market was built and completed yesterday SEE (http://www.planetminecraft.com/project/market-place/) for more information
>Nether temple underwent a revamp with the ceiling being redesigned to give a more greek look and the floor having the purple wool as promised; the glass dome in the roof has been scrapped and kept for a future temple etc.
>Grand library and Elder council has been completed SEE(http://www.planetminecraft.com/project/council-of-elders-and-library/) For more information
>The inner Piston defensive wall has been SCRAPPED FROM THIS PROJECT it will likely be used in a future city or small town.
> Small Rail line has been built to connect Serenities hope with Citedal Plaza.
> Moat has been created with retracting walkways. (SEE PICS)

Update #3
Crafting hall and guard building built and walls completed the only thing left is the housing. because i'm out of ideas and cba i am going to finish here. there is no more i can add that will 1 look right and use the space left withough it feeling cluttered. however if someone finishes building anything in the plaza please let me know .

PLANS
over the next few days i plan to design and build a
>PVP arena in south eastern open area
>Residential buildings erected in the small open arena next to the south gate.
>Add Pub and more shopping areas along merchants way.
>fill moat with water.
>Widen Paths
>Possibly build emergency redstone circuit to close bridges and close gate houses

Additional Notes

ADDITIONAL CREDIT: - Neztech for the piston Gatehouse idea.
- FyreUK (Youtube) - Nether temple and Rail line idea
- Toasttify (Youtube) - Selfbuilding wall
- Octobre79 (youtube) - Citedal Tower