Mixed occults

Everything TS4 does is amazing. I love the game and all the content, even with all the chaos with the fairies and updates and ailments its my favourite game of all time. But seriously though why haven't we been able to mix of sims occult dna like half Alien half werewolf or half fairy half mermaid. And why aren't plant sims a regular occult. Im a long time player since TS1 and sim city days ive seen the craziness of TS 2 and 3. Please TS4 devs stop playing these games with us about ts5 doing the whole will they or wont bs. Give us multiplayer (with cross platform play) and mixed occults and maybe throw in a little more story line play thats aren't challenges or scenarios. Also side note please give us better rounded roofs and walls