I think apart from the two sjr has recommended your only other possibility is Newnet. Three possible options:-
Business B. A bit pricier , but if you signed up on a one-month contract you could change to annual if happy.
Home SO if you can schedule some of it into the 2-7am slot. If you find occasionally you need more than 20GB in 7-2am then the page shows you the units you can buy extra. Still costs out OK compared to the other two ISPs.
Home S not really in the running over 30GB unless that is rare, but cheap. Especially if you occasionally stay under 20GB such as when away from home.
No idea about game pings as it seems highly dependent on where in the country you are, and I'm on interleaved as well. Re speeds then evenings and weekends are actually faster than daytime for me. (Reason is they are primarily a business ISP so when they all go home things improve).
I sync just over 7000 so have an IP Profile of 6000, I presume you have 7150. Daytime speed test results nearly always over 4000, evenings and weekends normally around 5000. Around midnight about 5300. Taking overheads out of 6000 that's pretty good IMO. BBMax test which seems to include overheads shows 5700-5800 at the high speed times.