There is no way that Dara O'Briain would want, or be offered, the job so stop torturing yourself !
I have not been a regular watcher of the LLS in years. I assume the core audience to be people older than me. That consitituency remains from Gay Byrne's time and need to be catered for.
The next host needs to be an experienced broadcaster and a safe pair of hands. Gerry Ryan could get it, though that could alienate many of the existing viewership. Most likely to be someone already in-house, more of the same.
I suspect that, in a year or two, perople will be looking back fondly at Pat's time in charge, much as they currently do at Gay's, even though in his time the show was uneven.