How similar do names have to be before they are considered too similar? I realized that a lot of names in my current novel sound but don't necessarily look similar. For example the protagonist is Dacie (Candacie even though it's pretty much never mentioned) except by some of her friends who call her Dace. However her best male friend is called Chase. I know I shouldn't be this conscious of the fact that they rhyme, especially as Chase doesn't call her Dace, and isn't in contact with the people who do but are they too similar sounding?
Difficult to say, I should read quite a few pages to be sure. At this point I probably wouldn't mix up Chase and Dace. Generally people here recommend to make sure the character names are different enough, but whether it's the transcription or the phonetics that matter more may even depend on the first language of your reader since so many people can understand English nowadays. We could see and hear the names so differently: Chase: [tʃeɪs] or [khase] or [sha:s] or something else... Dace: [deɪs] or [da.se] or [da.ke] or [dʌs] or [da:t.se] or something else...
If I were reading that book, I probably wouldn't have problems with the names being too similar. Personally, I would only have a problem with the names being similar if they were "visually" similar, rather than phonetically, i.e. Daniel and Danielle. If the book were being narrated to me, Dace and Chase might sound too similar for me to tell the difference sometimes. But everyone's different...
Just make them different characters. Your goal should be for your readers to know the players in your tale. As long as Dace and Chase aren't cookie-cutter characters of similar archetypes you'll be fine. At the end of the day people will remember the character's personality and actions rather than a name.
Here is an invaluable resource, a random name generator, using data from U.S. census http://www.seventhsanctum.com/generate.php?Genname=quickname I usually set it to 10-20 results, so that I can pick over each of them and find of first/last name combo I like, and it usually takes two or three generations to find a name I like. But, it won't be a name out of my imagination, which only has room for 10 girls names, half of which are Rachel. I don't even know a Rachel.
Hey, I don't think those names are too bad. I would know, too, because I was working on a project--and still want to return to it eventually--in which the MC's name is Zane, his son's name is Zeke (Short for Ezekiel, which he doesn't answer to much), and Zane's Alter ego calls himself Shane. That's all well and good if you don't see them much, but the whole thing went bad because they're the 3 central bodies and driving forces of the entire story. Then of course I made it more convoluted and had a terrible accident cause Zeke's soul to split and merge with half of Shane's, resulting in a messy character triad in which the three main characters are all expressions of the MC (and aptly connect back to him and to each other)... That's the relationship I wanted, but it doesn't translate well outside my own head. The characters are different enough to distinguish in dialogue, but when you have all three together in an intense scene it's a debacle of Zane... Shane... Zeke... Shane... Zane... wait who did what? Ha! So take it from a guy with a bad naming convention, as long as they are visually distinctive, and their character voices are the same, the rhyming sound won't ruin it. It's only possible to confuse it if you're listening instead of reading.
