Originally Posted by GrayAnderson

Mental overhead goes on my balance sheet as a non-cash expense (kinda like depreciation). And I'd weigh that against the benefits (I can track a lot of stuff in my head)...

However, a non-trivial consideration emerges..
The four cards tally to $2000/yr in fees. That is a lot. However, the offsets are as follows:
Resy: $20 DL Reserve Personal, $20 DL Reserve Business, $10 DL Platinum Personal, $10 DL Platinum Business. $60/month, assume six months' full usage (assume the other six months just don't work out or crediting glitches). $360/yr.
Rideshare: $10 for each card. Up to $40/month. Assume three months' full usage (lots of breakage here due to limited rideshare use, but useful in flurries of short rides). $120/yr.
DL Stay Credit: $200 DL Reserve Personal, $250 DL Reserve Business, $150 DL Platinum Personal, $200 DL Platinum Business. $800/yr, but presume effective cost of 20% due to room rate constraints, incomplete use (though I already know the properties I'd be using this at - I stay at some Choice hotels a few times a year but the juice just isn't worth the squeeze with them), and opportunity costs vis-a-vis hotel reward earnings. $640/yr.

That's $1120 in benefits offsetting the $2000 in fees, with limited opportunity costs, for a net cost of $880. And for that net cost of $880, you get $10k in MQDs (Gold status). That only requires $5k in further MQDs to get to Platinum (with the four RUCs) if desired, or the ability to just always cross-credit to VS if that is preferable, but importantly it preserves free SDC (and, if crediting in-house, extra lifetime miles).

Presuming the benefits of the companion coupons are null (not a safe assumption - there should be at least some residual value, even if just in gifting to some friends) and ditto the guest passes (eight of them), the 30 "SkyClub days" (essentially 13-15 round-trips*) probably functionally equate to a SkyClub membership (I might exceed that number in some particularly froggy years, but it won't be common - that's nearly 10% of all 24-hour periods covered).

Honestly, the math might work here. The effective net reduction in cost of about $720 for a four-card hand is a serious consideration.

[Somewhat comically, I don't actually [i]need this until '25 (SkyClub) or '26 (status), so it is not an imminent consideration.]

TL;DR: Delta might be easing their way back into my good graces. This is very much TBD, however, and as noted there's a certain amount of mental overhead. I guess it will come down to some questions over at AA (and what AA's situation looks like as they phase out F on the 321Ts).

*My IRROPS luck will invariably bite me here, so I assume at least 2-4 times/year I'll end up burning an extra "day" amid flight chaos.