Knowing that 99% of people who went to big mountain actually became brainless zombie I don't think it's the best idea.
Back to the topic.
If I was the character that I last played, the Courier (I literally named myself Courier), I would become the Elder of BoS and conquer the Mojave with my army of guys equipped with Power Armour and energy weapons! Having 100 speech I will convince my every single companion to join BoS, except maybe Boone, NCR hates BoS, and Boone is from NCR, but we are best friends, I already did his quest so he probably will join me, and Enclave, Enclave and BoS hate each other but Arcade might convince his not-so-purely-Enclave-but-just-love-to-fight old friends to join me. Using my repair skill and materials I will reverse engineer Enclave power armours and merge them with T51 power armours, to be better, I will also try to recruit super mutants from Jacobstone, altough, knowing Marcus, he will not let me, well, I will at least try to make the proffesor guy from the lab to make me the same kind of stealthboys Lily has, the one that you can turn on and off, and never wears out, he will probably be happy with it, but I will scare him with vision of complete carnage. With my army I will destroy the entire Legion, and give NCR opportunity to give up, if they don't, well, I won't ask twice, if you know what I mean. With my group of brotherhood scribes (They probably have high science skill, I don't really know) I will hack securitrons to make them my minions.
I might get mad with the power, but it's not like my character wasn't mad with power before.