I'm old school and still build prototypes (as well as designing my code on paper first). Most of my stuff is more than just an 'Arduino + Shield' so I tend to end up hanging a prototype board onto an Arduino, or stuffing a Nano onto a prototype board. I also use some of these as almost disposable prototypes...
It's a useful little board but sometimes a bit small. As is the Arduino prototype board.
So I'm thinking of making my own and wondered what features I may have missed. So far I have...
mega328 in DIP
DC input jack
USB (power only) jack
2-way screw terminal for DC input
on-board 5V or 3V3 regulator (likely switching using a Recom part)
6-pin (FTDI) SIL header with DTR reset capacitor
6-pin AVR ISP connector
Prototype area with power busses
Easy access to all AVR IO pins
Crystal and capacitors
Area tracked for IDC ribbon 'output' connectors
Probably eurocard sized (160mm x 100mm) plus eurocard mounting holes
Area tracked for screw terminals
Unallocated buss lines for other power rails
Can anyone think of any other useful general purpose features?
I also wondered about doing an SMT version for the new 4809 as a second-gen Arduino version.