what is the best trisquel laptop for my purposes?

What laptop are you talking about? A few different laptops I can think of are shipped with Trisquel.

In any case, you can set up a Trisquel installation however you want with net install, including making it text-mode by default. Since Trisquel includes no non-free blobs, any other GNU/Linux OS with a sufficiently recent kernel version will work on a computer Trisquel works on.

The only laptop which has earned the FSF's Respects Your Freedom endorsement is from gluglug.

* https://fsf.org/resources/hw/endorsement/respects-your-freedom
* http://shop.gluglug.org.uk/

I'm pretty sure any of the free distros can do virtual terminal switching well.

* https://gnu.org/distros/free-distros.html

I think the best combination for you could be a ThinkPad X60 with Trisquel GNU/Linux, but you can also look at some other choices. On the laptop side, look for the coreboot supported models, like the Lenovo X201, or some Google Chromebooks (e.g. the HP Chromebook 14).

As for the "GNU/Linux" distro, it depends on your preferences. If you want a free Ubuntu derivate, go for Trisquel. You can also use plain Debian GNU/Linux, which is completely free, except that it does provide non-free packages through its non-free repository. You may also like Parabola, which is a free Arch spin-off.