Upload & Sell: On
If you can find one of the older discontinued Gitzo 3541LS tripods and get a good price on it, that is a way to save a little weight. But the new Gitzo 3542LS is the same weight as the Really Right Stuff TVC-33. All three are similar in their maximum height. If you want 4 leg sections, you are right that the RRS TVC-34 is a little more weight than the Gitzo 3542LS. Remember that the RRS tripods use larger leg diameters than Gitzo for the comparable series, so they perform better.
Your future need to support a 300 f2.8 lens would point toward one of the larger series of tripods. You might skimp by with a TVC-24, but I would not consider the Gitzo 2541 for a big lens.