On the other hand, I just looked and it turns out the Duelling Sword do not get a expanded crit range, only the usual one for swords (19-20x2). So including Aldef in it was pointless. I will either remove it or exchange it for a regular Fighter dip and specialize in the Estoc instead.
The advantage of the dueling sword is that you get an exclusive feat with +2AC and an initiative bonus, as well as having that weapon plausibly available in good quality due to the campaign.
The estoc seems like the best magus weapon numbers-wise but I'm not quite sure how available they are at higher enhancement levels, and unless you're Sword Saint you need the exotic proficiency to use it properly.
I started playing an estoc Sword Saint, pure dex/int, but I got discouraged after seeing his reduced spellcasting.
So now I'm a regular Magus, str/int build, I'm using a +1 scimitar but I haven't picked any feat for it yet to keep my options open.
What I really like with the proper Magus class is the spell recall ability, fueled by the arcane pool. It's really good and gets even better later on.
You can even swap a spell on the fly, recall it, and use it immediately (which I'm pretty sure you're not supposed to be able to do until you get the improved recall).
Plus, you get to wear medium/heavy armor later on for free.
One thing I did though, to make soloing bearable, is mod the game to get double mob exp. I did that after I noticed that I got about 6 times less exp from a Worg than the proper exp reward from the tabletop game. So now I still get about 3 times less exp, but it's already a lot better and now I don't have to worry about wasting too much time on grinding random encounters.
Modding was a bit arduous to get into, but in the end I managed to use dnSpy to find what I was looking for. There are in-built multipliers for each source of exp : mob, boss, various categories of quests, and skill exp, so I only had to tune "mob" from 0.75 to 1.5.