Yeah, this is very personal to each creator. As a patron, I don’t mind if the Patreon is a tip jar. Bottom line is I’m supporting the artist when they do that. There are times when I have pledged to a higher tier to get a reward and then never gotten the reward and that’s not cool. Some people are of a really good business mindset and they’re good at following through on rewards and some people just want to make their art without restriction. There is nothing wrong with either. You have to decide if you’re wanting to sell a product/offer a service or just allow people to support you creating art. You can have tiers without extra rewards just so people can see that they can pledge different amounts if you choose the latter.
As a creator, I have a combination. All of the art, lore, works in progress, basically all content is listed at my $1 tier. But all of that same content is released as a public post so anyone could follow me and get it for free. I don’t mind because I don’t want to keep people from seeing it. I also allow followers to take part in my regular polls. I want people to engage with me and what I’m doing and they don’t have to pay to do that. I understand people can’t pay every single artist they want to support. But if I have them as an active follower they are more likely to become a patron in the future when they can afford to do so if they’ve found value in what I provide. I leave that for them to decide. I have 16 patrons who pledges range from $1-$20 even with all content free. I have several (don’t know how many exactly) followers who comment, vote in polls, and give me hearts from time to time. I try to be as welcoming to them as my patrons because sometimes all you can afford is moral support and I can appreciate that too.
On the other hand, I have a separate Patreon for NSFW art and that is all paywalled. I put public posts with smaller censored art, but the majority you have to pay to see. I also instruct them to follow my “free” Patreon to get access to the content there for part of their reward. I just started that Patreon in February and have 2 patrons pledging $7 and $20 respectively. They were originally pledging at my other Patreon and moved over for the “bonus” content.
Either way you decide to go will work so long as you consistently update and promote. I think sometimes people worry about making compelling rewards too much and really if they just focus on makin’ great content they will do fine.