I have 2 daughters with multiple hemangiomas, my youngest's (6mths old) are on her forehead and scalp. We saw an expert (Dr Wagner) on Friday and the recommendations were to start propanol to stop further growth and reduce their size then consider laser therapy if veins/redness remains (she's thinking 1-2 sessions more than likely will do it). It looks like the propanol has been very successful on your daughter, you could be able to avoid surgery by continuing it until the growing/evolution stage (think this is around 12mth or so? not sure though) is over then consider laser therapy if required (if you think Timolol isn't doing anything discuss taking her off it so it's less drugs going in her system). What I think you should consider is which option would give the best end result and discuss this with an expert - surgery would leave a permament scar, would propanol or laser leave less markings? This will really depend on each hemangioma; for example my older daughter (3yrs old) will be having surgery on the hemangioma on her arm (then laser too as the Dr. just wants to remove the very damaged section and laser should take care of the rest- to avoid taking too much skin off), the tissue damage is too great to be resolved with just laser and a surgery scar will be less noticeable than leaving it damaged as it is. However if she had been on propanol back during the hemangioma's growth we might have been able to avoid this.
However it's a very personal decision; this is just my point of view - you have to do what feels right for you. Maybe see another expert for a second opinion? Best of luck!!