For basic sign work, I see a tablet as slightly over-kill but we still use one as it's integrated into our workflow. On introductory meetings, it's rarely used. We always have something to leave behind.
I still take notes the old school way - pen and paper...
Depends on the work you do, but it looks like you do some sign work similar to ours...
We use an iPad/Apple Pencil because we are all Mac... during meetings, we sometimes have the whole creative team - including architects, marketing, in-house. The iPad helps when rummaging for certain code and sign related information we don't want to carry in printed form - the ADA code book is 1200 pages for pete's sake, let alone the fire code, health and safety and municipal code for the project. We like have that information in case it's discussed. We can go online and show the client work that has been done before, or reference other ideas done by others. We use it for survey work, measuring, location plans using Google Maps, we can access our office computers on the fly, hook up to most office monitors for presentation. We also record some parts of the meeting so we have a record of what's expected. Larger projects tend to get a lot of creatives having input, we want to make sure everything is addressed prior to showing up to a meeting that we at least considered it.
We rarely if ever do it sketch something in front of the client... it may happen during the meeting, but never shown. We try to get all the information, then go back to the office and think about it before putting any ideas on paper/tablet... but we are not selling signs... we sell services prior to fabrication and installation
We usually have a project by the time a meeting like that is in order, but we always bring something to leave behind in case other creatives can use our services.