This kind of thing:
https://www.attackpoint.org/sessiondata.jsp?sessio...
You fill in the front bit.
Most north/south streets coming out of Cedarvale Park end up crossing the Beltline.
Glen Cedar is probably best.
The first 5ish km would be a lovely, cruisey downhill...perfect to warm up.
Then a long slow uphill grade home.
Satisfying.
You can attack it via different creeks/ravines of the Don to mix it up.