どうも ... そうだ/ ようだ/ らしい => It seems, probably N3
Speculation
かどうか => whether or not ~ N4
たらどうですか => why don't you; how about ~ N4
Invite and advise
どうせ (のこと) だから => Because eventually have to ... N3
Invite and advise
どちらかというと => Overall, it can be said N2
Evaluate
どうして => why; for what reason; how N5
と~と~どちら~か => Comparison N5
Compare
どうせ ... いじょう/どうせ ... からには => anyhow; in any case; at any rate; after all; no matter what N3
Necessity, obligation
たしかに/なるほど~かもしれない => might; perhaps N3
Speculation
しかしながら => however, nevertheless N2
Things do not match the prediction
なぜなら(ば)/なぜかというと/どうしてかというと/なぜかといえば => because; the reason is; if you want to know why N3
...どおし => Throughout N3
Continuous