openings for ~1000


Not at all true that you are playing the main lines up until move 20. For example this game:
Did not follow any main line up until move 4. This was a Sicilian opening.
You are not consistently playing the Vienna opening either. Here you play 2.Nf3
In this game you play the Vienna and your opponent blunders on move 3
So I do not understand how you are getting the feeling that you are playing main lines for the first 15 to 20 moves.

Vienna is good, perhaps study some Italian, especially Guccio Piano stuff I guess that will compliment Vienna (d3 stuff). Just assuming many Vienna games transpose into these quiet italians.
Scandi is a bit hard to play but you should treat it as a propper opening and maybe study some master games in it (not cheap trappy Scandi stuff where the queen moves a milion times)
Also master games in the Exchange Variation of the Caro Kann, pawn structure can become similar to the signature Scandi pawn structure.
Scandi is considered inferior at top level but it's actually very dangerous at amateur level because people have misconceptions that it's a weak opening.
Anyways, no need to change openings.. All openings are fine what is not great is fiddling around between different openings and gambits..
So to sum it up:
Look at master games in Vienna and compliment with Italian Guccio Piano with Nc3 (and not c3- 'Pianissimo')
Look at master games of Scandi and compliment with Exchange Caro Kan...
The purpose of the opening is to get a playable middle game.. don't think opening choice will decide the game

White e4: Bishop's Opening against e5, Delayed Alapin against d6 Sicilian, Kramnik against e6 Sicilian, Two Knights against Caro-Kann, Advance against French, Austrian against the Pirc, exd Nf3 d4 c4 d5 against the Scandinavian, decline the Nimzowitsch and play the Scotch, Four Pawns Attack the Alekhine's (e4 e5 d4 c4 f4 fxe4), c4 Nc4 d4 f4 Nf4 the Owen's, Averbakh the Modern and try to transpose to a KID.
White d4: Accelerated London against d5, Trompowsky/Torre against Nf6, generally don't play d4 theory if U1400.
Black e4: find one and stick with it, I wouldn't quite recommend the Scandinavian but it isn't terrible.
Black d4: Indian Games. KID, OID, etc.