Its a good idea, to have an advanced career. If your having fun with it, thats what is important.
But lore wise. Engineers and Runesmiths are two different Guilds. In the Dwarf society I have read Runesmith is a long term education can take decades or even a century to master it. But nothing to stop a Engineer going the Runesmith path. Cant see them going the other way, not unless they are such a failure at the craft.
The highest rank of Runesmith are so revered that only a King, Grudgekeep and Lorekeeper are higher in prestige to them.
Engineer, now I agree, that needs a higher rank. Only 2 engineer careers means you have to train dwarf engineering twice in a career so lose out on one specialization.
What is your idea behind the Runegineer, seems you thinking of it as a rank 5 career? The traits on you card make it a rank 3 career though. Should be elite or even heroic instead of advanced.
Dont get me wrong, i love the career. I would even use it with that modification, also having both engineer careers dedicated as well as the runesmith careers, would be great too.
Currently the flow is
Basic Apprentice Runesmith -> Intermediate Runesmith
Dwarf Engineer -> Dwarf Master Engineer
I see Runesmith ending in a type of Master Runesmith, a high social rank as well, hmm i just read a dwarvern book on the War of Vengeance that mention these special runesmiths. They were ancient and revered.
I see Engineer ending up in Dwarf Engineer Guildmaster, which is very much a political position.
High level runesmiths have a special magic, not sure how it works, but the book i mentioned did describe a staff, dispelling and electricity blasts. There any runes like that in the game?
Sorry, I love dwarves and their lore, so get carried away on theorycrafting.