Interactive Holographic technology,is the new way foward,by 2260 all humans will have a holographic interface,where you actually walk the net rather than browse it. We will all have data processes implanted in out heads so we can go online where ever we are without the confines of the bulky pc,just imagine walking the pages of the PCA forum with interactive guides and helpers,you could actually see a virus up close and personnell,and actually see it get destroyed,by the "interactive guards". No more click to open pages,simply use the verbal interface and ask for what you need. Everything is done in a nanosecond of thought.
Yes SATA is better than IDE its faster and the cables are smaller helping increase the airflow for cooling. PCI Express is better than AGP faster and you'll notice most manufacturers are designing new graphics cards as PCIE only.
your question is almost academic. The mobo you buy will either be for AGP [as most say rapidly going out of use] or PCI-E [the current new standard] or whatever the next thing is going to be. I would not advise anyone at this time to go for an agp setup as they are becoming difficult to obtain and if the card should die in 6 months or so you may have to start again.