I have had a lot of luck with the Fidelity 500. I changed from a brokerage of ~40 random stocks and bonds to mostly FXAIX, VTSAX (there is a fee to buy but I am holding for a long time so it didn't matter to me) and some in a whole market bond fun, but not much.
You could throw some Contrafund in there if you felt so desired. Might have to much risk though.
When I look at FSTVX on Fidelity, it takes me to FSGTX (Fidelity Intermediate Government Income Fund) so not sure if the fund is closed to new investors or what.
The bond fund I have is FTBFX (Fidelity Total Bond Fund.) Has a little higher Morningstar rating and returns than the Government income fund. Exp ratios are the same. That might be something to check out.
The three fund option is somewhat enticing. the Fidelity ZERO Total Market Index Fund has many of the same top 10 holdings as FXAIX with no expense ratio.
I have been happy with my set up but I should say when I do start poking around on Fidelity I get tempted to change some stuff, but at the end of the day, I guess I try and find something I am generally happy with and go with it.
It's like eating at the Cheesecake Factory. I don't need a 62 page menu!
Good luck!