We've flown Silver annually since 2016 (except 2020), and we've only had a few minor issues. The newer plane they are flying is a much better experience. With this said, we have always used a code share option through American - so we don't touch bags on the way down and only pay for them once on each leg (since it's international, our status on American doesn't cover the bags). If Delta has a code share with Silver, you could obviously buy some of the tickets through to EIS with code share and pay cash for the rest. Just a thought - good luck!