Would you care to name those 4p engines that you are mentioning?
It's difficult to make a one on one comparison in a vacuum. But, if I were to list 4p cards that gain above average value and (close to) 1 strength/damage each turn, some of those would be:
- Iron Falcon Infantry (slightly weaker because it's neutral)
- Dwarven Mercenary (not to mention using this with double Justice)
- Lyrian Arbalest (to a lesser extend, but damage is more costly)
- Garkain (easy enough to keep bleeding on)
- Sly Seductress (even more threatening when bonded)
- Magne Division
- Thrive (Nekker) and Harmony (Dryad Fledgling)
There is nothing quite like Redanian Knight, so there will always be situations where one or the other is better. However, when you look at the average value gained, the card doesn't rise (far) above the others.
PS. If you want to talk about "what-if" scenarios, instead of just a flat suggestion, then I can move the thread back to gameplay. However, note that the devs are more focused on the suggestions forum for -well- suggestions.