I've been on weekly humira (one 40mg pen every week) for a year now. I have zero side effects and my UC is in clinical remission (my labs are normal..still waiting on a follow up colonoscopy).
I don't think going to weekly humira from bi-weekly necessarily has any added risks. Many of the reasons patients go to weekly is to maintain acceptable drug levels that can't be accomplished from taking it every 2 weeks. In many cases patients process/burn through the drug much faster. Additionally, weekly humira is more common than you think and not necessarily a high dose. A high dose would be someone taking it every 5 days or 2 pens per week.