If the pan will be dropped - always a good idea to replace the gasket and replace the filter. Pan is already going to be off, might as well replace the filter while it is accessible.
Like I mentioned, if you can't find a shop that will do it or has the equipment - a cooler line flush will be OK, just make sure they take the pan off to clean and replace the filter. Make sure that you can either see them take the pan off, or provide you with the old parts. Unless it is warranty work - you can always as for the old parts back by law.
My 2002 Corolla - I use Toyota Red - in the others, I plan on running either red or pink. Pink is already prediluted - so it can be a challenge to get all the water out of the system in order to maintain the correct concentration - but it is doable. Which one you should use - up to you and what you can find at a dealership. From what I gather - it can be hard to find Toyota Red now that all Toyotas have switched over to the premixed pink stuff.
Per spec:
From ORIGINAL Factory FILL:
Toyota Red = 50K miles, 36 months
Toyota Pink = 100K miles, 120 months
For subsequent drains and refills:
Toyota Red - 30K miles, 24 months
Toyota Pink - 60K miles, 60 months
I generally try to stick to that schedule to avoid any issues, but many other owners have commented that these can be considered somewhat on the conservative side. I've flushed and refilled with Toyota Red at 36K mile intervals (2 years for me) - with zero issues. The Matrix was recently switched to Toyota Red - plan is to follow the same schedule as the Corolla, or switch to Toyota Pink down the road. It is actually weeping coolant by the water pump, so I'll keep an eye on that. My Rav4 is still running the original fill. Won't worry about that until it gets closer to 100K miles. No weeping like the Matrix - knock on wood.