*Texas doesn't keep its land records in Virginia, at the Bureau of Land Management, like the other 49 states
I'm not exactly sure what is meant by this. Each state keeps their own land records. The federal Bureau of Land Management deals with federally-owned land, not keeping track of land records.
However, one thing that is true is that when Texas became a state, one thing it demanded was to retain ownership of its public land. Most other states west of the Mississippi had to give public land to the feds. What that means today is that the federal government owns very little land in Texas (and what it does own, it had to buy); compare that to Nevada where the feds own 83% of all the land in the state.
*Texas has its own power grid
*Texas is a net exporter of energy. It has oil, natural gas, coal, plus lots of wind and solar.
These are both true.
*Only one state is allowed to fly its flag at the same height next to the US flag: Texas.
This is an urban legend, and is false. Flag etiquette--and it is only that, etiquette; it has no force of law--says that all state flags (or any flag, for that matter) can be flown at the same height as the US flag, so long as the US flag is given the place of honor, which is all the way to its own right, or the observer's left.
*Texas could be completely independent if it wanted to be
Kind of a broad statement. Do you mean it would be economically feasible? Probably so. Do you mean legally speaking? Probably not, at least not without a war.
*Texas would be *better off* financially if it broke off with the Federal Government. For every $1 of taxes it sends to Washington, it gets back less than a dollar. Other states, Missouri for example, get $2 for every $1 they send. So states like Missouri would go bankrupt if they seceded. Texas would actually be better off.
This is true, but only to an extent. In 2014, for every $1.00 Texas paid in federal taxes, it received $0.94 in federal spending. So it would be better off, but not by much.