take the Vagabond
Based on the experience you’ve listed, I don’t think you will have any problems doing it yourself. You can always quit early if you get tired of being by yourself. The logistics can get complicated, and an outfitter would be a help there, but otherwise, just think ultralight.
At 42lbs vs 58lbs for the two boats you mentioned, it’s a no-brainer for me- I’d take the Vagabond, and since its a solo, it will be a better choice in any case.
You don’t mention the length of your proposed trip, so its not possible to guess how much gear and food you will want to take. there is a big difference in planning a 10 day vs a 30 day trip. The longer you are out, the more important the luxuries and spares become. Also, the time of year influences what you bring, and affects the weight and volume of gear. Cold weather clothing and sleeping bag, vs mid-August can be a big difference. Regardless of how much gear you bring, you want to plan and pack “smart” for portaging. Eliminate “loose” items- everthing should be in a pack for partaging, or lasjhed to the canoe, otherwise, you risk leaving behind or losing some vital piece of gear. Small items can be kept in a fanny pack straped around your seat. For a solo canoe, I’d recommend one large pack, and one small to medium pack, so that you can trim the boat effectively for wind conditions (bow heavy into a headwind, stern heavy with a tailwind). Everything should fit below the gunnel line, to keep a low profile in the wind. The number of packs also depends on your physical condition, as you don’t want a pack too heavy to carry - might mean bringing 3 packs instead of two, and making three carry’s across the portages. Better to go light over the portages if you are travelling solo - less risk of injury. I usually go through a pack/repack/re-repack routine, till I get my gear down to where it needs to be.
I’d agree with the info given above about where to go. Either Quetico or BWCA would be your best bets (there are good guidebooks for both areas, and they will provide info on obtaining permits, recommended routes, maps, etc). You can do a search on this site for numerous postings with lots of useful info covering permits, customs/border crossing , bearproofing your camp, etc. I’d avoid Woodland Caribou and Wabakimi till you get a few trips under your belt. I’d also avoid Voyageurs NP, as that is mostly big water and wind can be a bigger problem there, though wind is going to be an issue wherever you go. Its quite common to get “windbound” for a day, or maybe several days-again, its best to be cautious, and you shouldn’t be in a hurry anyway. The idea is to enjoy your trip, not turn it into an ordeal.