After about 20 hours of testing...

[Mind4eva]

... I have to say that, to a certain point, the game is pretty much fun! This certain point is when the colony is stable (about 11 people, having constructed everything necessary, no problems in defending the colony from raiders etc.). This brings me to my first suggestion: What a bout a meta-goal? What about achievements? Something that motivates to go on with the colony. Easiest is to have more events that provoke action.
Whatever, here is a list of some things that were striking/missing while playing:

1.) A way to get rid of corpses, e.g. a funeral pyre. The graves are a good way to bury colonists with dignity, but those hundrets of the raiders' corpses...
2.) A kitchen/cooking meals. Well, read it before, and it seems to be in the game in futre versions.
3.) A recreation room and things like furniture to spend the colonists' leisure time. They need to be happier anyway.
4.) Where to put weapons that were dropped in action? There are masses of weapons on the battlefields.
5.) A mode to activate for the single colonist to spend recreation time. That makes it easier to stop working and to prevent the colonist from mental breaks.
6.) Automatic lamp lighting, means that lamps are switched on only in that moment people enter the room -- or manual swichting by the colonists themselves.
7.) The turrets are demolished too fast.
8.) Additional events.
9.) Toilets?
10.) What about repairing weapons? As the crafting skill is not yet effective I assume that it could be in future game versions.
11.) When having opened the window of the researches, overview, codex -> no time pause; can be done manually.
12.) I liked the editor in Tony Hawk's Pro Skater 2 - and I want to create myself in this game, too! What about a personal editor?
13.) I think water is more important than just food!
14.) More colours for the carpets. In general, more things to make the colony the colonists' "home sweet home".
15.) I saw animals/droves spawning in caves. Strange thing.
16.) I had performance problems after about 3/4 hours playing without quitting the game. The game started lagging. Could be my Computer, but maybe the game. Dunno
17.) I'd like that it is displayed since when a character is a colonist.
18.) What about the idea of multiplying. I mean the dirty sex topic of the 24 years old female Marine who is in love with the 56 years old Scientist *irony*. But damn, love is all around!
19.) I'd appreciate that colonist can learn certain skills they are not capable of. Otherwise I just have to "amorably" kill all nobles as they to nothing but eat and sh**!
20.) Is there a story mode planned?
21.) Many games I played had a multiplayer. Sometimes this was the only reason why I bought the game. In some other cases I was sick of having played the single player a thousand times, so I was happy about some time with the MP. There might be a way to implement a MP in RimWorld -- golden times for LANs
22.) It was annoying when the were e.g. 4 weapons, 5 corpses and one mine on one spot. I had problems in selecting what I wanted to interact with.

Thanks for reading! Sorry, if there are any mistakes in spelling or in utterances! Had a beer -- it's Saturday, dudes! Cheers!

[Galileus]

It's a pre-alpha. "Add more X" is not a suggestion - it's a plan.

As for the rest - you managed to hit something already proposed and/or discussed before with each and every of your suggestions. Congratulations!... I guess...

[palandus]

If you have an excess of metal, you can build the graves put corpses in them and then place blasting charges near the graves. The explosion from the blasting charges annihilates the corpses leaving empty graves. Also works on Dumping areas to permanently remove debris and junk.

[Creepypastaanime]

you said you have no problem holding off raiders, so why should turrets be more powerful? also, you can put weapons in equipment racks, but only 2 per rack.

[palandus]

Raiders can get quite nasty though, if they have M25s and are out of range of the turrets, but the rest of the raider band has to close into closer range. Those M25s pick off turrets quite fast, particularly as turrets will begin to explode if brought to 20% or less HP.

Plus I expect that eventually raiders will get some even nastier weapons as the game develops. So having a turret that can handle itself, would be nice.

[Creepypastaanime]

it would be, but i think it would take away more than add, if there was a better combat system, then turrets could stay the same and that way it would simply make it funner.