I actually just had a usb connection problem on my last new Clip zip. Basically I had "crash" or "panic" or "blablah" message on screen while connecting and then sometime connection was fine, sometime not : the drive showed up in windows explorer as empty.
I eventually & hopefully permanently fixed this like this :
1- re-installed original sansa firmware
2- re-installed rb release including bootloader.
It did not work if I only re-installed release without going back to OFW before.
I believe you install builds manually vs release using Utility ? Then if you have the bootloader box ticked, it would match some of my bugfix.
That's very DIYish, very much like me computing wise. Hopefully someone will be more accurate...
About battery life : make a wps or a config file for bright sun light, at home, at night, etc... Recharge fully between30~20% left. Don't recharge above 60%. Don't use the player permanently plugged (maybe it's k if you leave the screen "always on") . Again DIY but based on reading technical data about batteries (Li-ion in Clip+) Builds might help as well but hardware optimization depends on you too.
One last thing : the impedance of your headphone is related to the output and consequently battery usage. Some headphones are best used with dedicated amp/preamp depending on the source.