First post, but i've been following any 328pb info as I (foolishly) used it on a new PCB design of mine. Might as well contribute what i've learned thus far.
I tried out the optiboot bootloader from watterott, it doesnt work in the IDE, but I managed to upload it in avrdude using -Ulock:w:0x3F:m instead.
Then I attempted to upload a sketch using FTDI, no dice. Could be something trivial like reversed TX/RX or something on my end, I need to read the datasheet again. I ended up uploading a blink.hex using ISP, and it works(blinks an LED!). I used the internal 8Mhz because I didn't have any low power oscillators in my hardware bin..
Timer 3 has a slight issue when I tried to use output compare. It's not OCIE3A like I expected, but just OCIEA. I looked at iom328pb.h and this also applies to TOIE, OCIEB, ICIE, for timer 3. Timer 1 and 2 are normal (eg. OCIE1A).
Sorry if any of this doesn't make sense, i'm kind of new to arduino/electronics in general.