To scale up without relying on redirects, my suggestion is to use free third-party or parasite sites where you can include a link to your main money site or pages. However, this approach requires Pinterest users to click twice: first on the targeted URL of the pin and then on a link within that page to reach your money site or page. Consequently, there will be a loss of clicks, but since many users do click twice, it is still worthwhile. It is not advisable to use URL shorteners since they are often banned on Pinterest. Moreover, even if a shortener is not banned, consistently posting shortened links can lead to the suspension of your account. Pinterest can easily detect these redirects since they typically employ 301 or 302 redirects.
Another option is to use sub-domains on your own domains. Pinterest treats sub-domains as separate domains, so you can claim a sub-domain on your Pinterest account. This can help enhance pin impressions, clicks, and so on. However, it is important to exercise caution as Pinterest has been known to ban domains in the past. While this is less common nowadays, it used to occur frequently. When a domain is banned, any sub-domains associated with it are also banned. Therefore, be mindful when using sub-domains.
It's worth noting that you can still use redirects, but be aware that if Pinterest suspects any form of foul play, the likelihood of your account being suspended increases significantly. So, while you can use redirects, it is not advisable to rely exclusively on them.
I hope this information is helpful to you.