I have a Juki 2000 which is just a straight stitch machine. I have a Janome if I need fancy stitches and whatnot... but I love my Juki. It sews an amazing stitch, can sew through just about anything including thick layers (a lot of other machines can not sew through like 8 layers of denim and if you make bags, that might be important to you) has the knee lift and scissors. The only thing that it's lacking is a tie off stitch but I'm good with that. I know it's a lot cheaper than the Brother you were looking at but it might be exactly what you are looking for - especially if you only need it for piecing.
It also sews really, really, really fast which is great. It's all metal so it's a heavy machine.
I've got friends with high end Berninas who love my Juki. A few of them are planning to get one. You've already got a longarm so I think maybe going this route might be a good way for you. It also has a 9" throat so if you are doing small projects that you don't want to put on the frame, you can easily handle it on the Juki.
Save your extra money and go try out a Juki. At under $1000, your extra money can buy a whole lot of supplies...