OP, to be honest, Silver is not what it used to be and hardly worth much. Even as a Diamond, my upgrade rate is dismal and we have a higher chance of getting shoved into a comfort plus middle seat.
Cautionary tale - as a Diamond, I find quite a bit of MQD calculation errors, to a point that I keep meticulous records of every flight using a finance app. Here are the common issues:
1) Airline surcharges - these are qualified amounts towards MQD, and they can be quite significant, as much as 1/3 of the ticket cost. I find that they seem to appear on DL-coded partner-metal flights.
2) Codeshared partner flight sold by DL on 006 stock - a few airlines are major offenders of not posting - China Airlines (CI) out of Taiwan is one the worst - they almost never post automatically and require multiple phone calls. I would avoid them but don't have a choice until Korean Air JV comes fully online. If Delta sold the ticket, you get full MQD credit for that segment.
3) Ticket changes - man, this is a mess. The system recalculate even the flown/credited segments because the change of the un-flown segments can change the fare for the flown segments.
One best way is to look at your receipt, and add up base + all airlines surcharges (not taxes, government fees, airport takeoff/landing fees), and that's your earned amount towards MQD. I have had multiple arguments with Diamond desk agents, many do not know airline surcharges are eligible. They usually act like a jerk and refuse to pass the information to Sky Miles desk. I usually get testy with them, at which point they reluctantly call Sky Miles desk and only to be told I am correct on the surcharges. I find Sky Mile desk seem to be pretty recent - the challenge is to get the front line agent see things your way and call Sky Miles desk.
It's an uphill battle to correct missed postings and miss calculations, even for us Diamonds. Best practice is always check within 1-2 days after the flight and don't wait to correct the mistakes.