Got Lenna's ssb and Butz ssb as well. Butz's pretty much matches Beatrix's sb but with an extra hit on it. Do the 5 hits do more damage than Rose of May? Also, can't see a time I'd use Lenna's Large medica over Rosa's, but we'll see.
Power levels for SBs are usually the same across characters, but are higher for SSBs/BSSBs versus regular SBs.
For physical single target SBs, they generally total ~500% (SB), ~800% (BSSB/SSB), or ~1600% (OSSB).
For magical single target SBs, they generally total ~900% (SB), ~1800% (BSSB/SSB), or ~4000% (OSSB).
In this specific case, you have:
Trueblade of Legend = 790% over 5 hits
Rose of May = 516% over 4 hits
As for the heal, 50% RES will be better for things which use a lot of magic (e.g. Adel). Magic blink will be better for things which use strong magic attacks rarely (e.g. Sephiroth).