What's tacky about it?! And to answer your question, yes. In my opinion, this will lower your success rate significantly.

I don't want to sell in my lifetime but when I die I want my children or whomever that gets my collection to get some use out of it you know? I also find personalized autographs really tacky.

So you dont want to sell but you want a higher value?

that doesnt make sense in your LOR just ask the celeb for an Autograph not dedicated

Would it be considered suspicious if I asked the celeb not to personalize? Its not that I intend to sell the item or anything but I would like the autograph to have a higher value than a personalized autograph if I give it to someone or whoever gets my collection after I die.