I am in the progress of building my first bike from scratch and am having some issues deciding on the bottom bracket/crankset combination.
My frame has a BSA 68 Bottom Bracket shell, track dropouts and my rear axle freewheel cog has a chainline of 41.5.
Now since this will be a singlespeed I'd like to have a decent chainline, from what I gathered finding 41.5 at the front is nearly impossible but at least a chainline between 42 and 43 should be doable at the front, making it run smooth.

I have the following requirements:

• Chainline of 41-43mm
• Very durable bottom bracket (I hate squeeking bottom brackets and it happened to me way to often, so I'm happy to splurge here - also this bike might get into rain, so a good seal is required)
• 175mm crank length
• would prefer a more "modern" look (so not sure about square taper)
• 144 BCD

Looking at this, I feel like my options are fairly limited.

Option 1: Miche Crankset

• Crank: Miche Pistard 2.0 (CSPA0B)
• Bottom Bracket: (heard bad things about the standard Miche Evo Max)
  • Enduro Maxhit BSA24 (BKSM-8112)
  • Miche Supertype Evo Max (BBSTE)

My issue with this option currently is, that I don't know if the Enduro BB would be compatible (which would be my preferred BB as I like the lifetime warranty and heard great things about durability), not sure if the Miche Supertype is any good.

Option 2: Rotor Crankset

• Axle: Rotor Track30 axle + spider
• Crank:
  • Rotor Vegast
  • Rotor Aldhu
• Bottom Bracket:
  • Enduro Maxhit BSA30 (BKSM-8142)
  • Rotor BSA Track30 Steel

Here I believe that both Vegast and Aldhu should work (in that case I'd take the cheaper option), but again am unsure with BB compatibility (Enduro again being my favorite) and to be honest, I don't think the pancake look will suit my bike.

Another (much cheaper) option could be the SRAM S300 - but it does have a BCD of 130mm and I am not sure about the quality of the BB (and I don't really want to buy another BB if it comes with one)...

Can anyone with some more experience maybe shed some light on my options above - if you have other suggestions please let me know as well.
Also I ignored Q-factor as I already found that my limitations are quite high and I am not sure how much it matters.

quit obsessing, lighten your wallet, then go ride your new bike.

end result....

ps.. there are any number of other track cranksets available.. pick one.