I've done this one too.
Going east on something to catch I-65, then backtracking west to catch I-80/94 eastbound, does not help that much with the congestion problem. The most congested section going east is often the short segment between the I-65 junction with 80/94 and the split where I-94 separates to go north and I-80 joins the I-90 toll road. The backup getting on to the toll road at that junction is what causes the eastbound congestion, as people try to shuffle from the high speed lanes across to the exit lanes going to the toll plaza.
If I want to go east on the toll road, I'll usually go up US-421.
You could go up I-65 to US-30, then across to Valparaiso, and SR-49 up to the toll road. Since I haven't gone through Valparaiso for many years, I can't say what traffic is like now.
I don't often use the 80/90 toll road, and when I do, it is usually to get from Middlebury to I-69, rather than to get into Middlebury from the west. That's something I would do only if I knew US-20 was not available and it would be the wrong time of day to try to get through Goshen.