preventing water from entering my no-step entry
You're good to go for now and maybe forever. The only water issue I see you ever having again is adding another French Drain trough next to the first one you did to handle those extremely rare flash flooding downpours. But, you did the right and most perfect thing to start with.

As far as the joists go, do a Screwdriver Stab Test...ugly doesn't mean shot. If the screwdriver just dents the wood you're solid and can simply clean and paint...the brick and brick's mortar are sound. If the screwdriver goes in or through or makes a hollow sound as it hits, it needs replacing.

You can bolt-on new sandwich scabs to replace the ones the previous owners did. Or, treat those joists like stairs and head them off to put their majority load out to further joists and put in entryway retainers or supports. Or, you could remove the bridging between joists and sister-on new joists that run the length of the basement. There's no reason to mess with floor space or moving ducts.