Most domainers use Moniker and Fabulous. I have accounts with both of them, also a 1&1 and namecheap account.
But I use Godaddy the most, sure you can find bad stories about godaddy...but godaddy is the largest register in the world...so you will have a higher percentage of complaints. They do have a bulk tool to register domains and if this is used you also get a free year of privacy I believe. (plus a nice discount) If you have a certain number of domains, you get a VIP rep to work with you. They also have .99 coupons.
Not sure what your looking for in this thread, since you have a reseller website with godaddy. (you can offer the same as them) I thought about the reseller website myself, but when selling and buying domains most is done with godaddy and moniker...having a website like handballjims domains just does not make sense unless you can offer something different.
