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Not sure if it's too late for this comment in relation to when you're sorting your strawberries, but 40-45cm is absolutely a good distance. Mature strawberry plants can get pretty big, and even at 45cm they can be overlapping, which can increase fruit rot, plus you'll give them more soil and less competition, which will result in stronger plants, so more and larger fruits and less disease.
That said, I plant my greenhouse strawberries at 40/35 as space is tight, so I compromise a bit to get an extra plant in each row than I would otherwise be able to at 40-45. The greenhouse is a more protected environment, so my thinking is they have less stress anyway.
Lastly, you said you'd abandoned your raised bed due to perennial weeds but that you were going to plant straight into the ground instead? I'm not quite sure what you mean, but unless you've got plenty of free time to weed throughout the week in the spring and summer then I'd personally get some weed membrane. I plant my outdoor strawberries through holes in weed membrane and I barely have to weed, despite having a plot infested with mares tail and couch grass. Some of it gets through the holes but not enough to worry about, and over time when I've looked under the membrane it's massively suppressed the weeds. If you don't do that I'm unclear how you won't just end up in the same situation as with the raised bed.
Also, after trying many varieties my experience (which may be totally dependent on my growing conditions) is that Marshmellow is a brilliant mid-season option (always super sweet) and Malwina is a brilliant late-season option (also very sweet, and a definitely unique flavour). Vibrant has been a good early-season option for me in the past, but I'm trying Honeoye next year too for the first time, which seems well-rated. I'm also trying Florence next year as another late-season option. Mara de bois (mid/late/ongoing) is also great. It gives smaller berries but with a totally unique bubblegum-like flavour. I've also found Sweetheart (mid) and Flamenco (mid) to be pretty good but not as consistently sweet. In my experience though Rhapsody, Rosie and Aromel are dodo (consistently bad flavour), while Albion is mixed and probably not worth it.