Your ideas are good ones. But the products are already there.
1) Watching TV on PC has been there for a while. The recent push of eHome or Media Center from Microsoft is the latest attempt in this category. All major PC and CE manufacturers have this kind of products which can do all the things you mentioned.
2) We have seen the projectors getting market shares mainly in business use. Home application is still very small before its brightness can compete with other large screen display devices. Your reasoning for such large screen used in TV is also in question. You can not keep the PC viewing angle when you watch TV, even HDTV. The ratio of viewing distance to screen size is more than 7 for SDTV, about 3 or 4 for HDTV. This is the distance at which you will not see the scan lines.
