I'd consider making sure I had what I needed to use lithium AA's in the Garmin & InReach for your short spike camp trips. Solar set-ups are nice, but it's kinda hard to justify packing a solar panel if the weather might not cooperate to use it. Lithium AA batteries are pretty light and not weather dependent. On most hunts I take the extra battery compartment with my Garmin Rhino 520 that takes AA batteries and some lithium batteries just in case the internal charge gives out. My headlamp is a single AA model, and my camera takes AA batteries so they can be traded to where they are needed.
I have a Goal Zero Venture 30 that works very well to keep my I phone 5 charged up. If your boat has a 12V outlet you could charge it up off that between spike camp trips. Since my headlamp isn't super bright I sometimes pack a Maelstrom MMR-X flashlight that the Venture 30 can re-charge also.
Your hunt a jumper pack that can charge off the boat while it's running, and be used to jump the boat if necessary might be a good addition. I take a small one on my river boat that has come in handy. It has a 12V outlet and a couple USB outlets so you could take one like that to your tent and charge your electronics. It would be cheaper than getting a solar set-up.
I have a lot of the Goal Zero stuff and it all works I'm just not sure it fits your hunt. If you decide to go that route here is a little info on what I use. I use the Yeti 150 and a pair of Nomad 20 panels to keep stuff charged up at base camp. I put the Yeti under my Megatarp and have the two panels set outside if I leave so it's pretty protected from weather. I can charge my Venture 30 off the Yeti 150 and throw it in my pack before leaving for a hunt. I have a Nomad 7 and Nomad 13 panel also. The 7 is pretty slow to charge much it seems, conditions have to be pretty good for a long while. I wouldn't recommend getting one, I almost always use the 13 or 20. If weight is a concern and I want solar it's pretty much the Nomad 13 panel and Venture 30 that goes. The Venture 30 can be charging off the Nomad 13 all day at camp and I'll plug my electronics (flashlight and phone) into it at night, throw them back in the pack the next day, and leave the 30 at camp to charge. Most of my short trips though I just charge the Venture 30 up and take it in my pack, don't take a panel. I'll be back to the vehicle or camp to recharge the Venture 30 before it needs it and I have the AA battery option as back-up. I haven't really used the 13 and 30 all combo that much.
Hope some of my rambling helps.
