You're welcome to PM me, but it's probably a good idea to bounce some high-level ideas here in public still. You'll get more answers from people with diverse experiences.
The list of features you mention are a good start. Map out the relationships by connections. For each connection, decide what device(s) need to connect to it. For example, recharging is "phone recharges from dc power" and maybe "dc power comes from ac/dc converter". Then "phone gets commands from ir port" and "ir port gets commands from ir remote control." This is a good way to make a system map of intended features.