opinion/advice regarding IUI/IVF

we have enough money to do ivf..but i was thinking about giving iui another chance..i did 3 rounds of iui all failed with femara..i asked my doctor if i was to do iui again would my protocol change..and he said he will change the pills to chlomid..i heard chlomid is bad for implantation due to making your uterine lining thinner..so that is wat i told my nurse and i have not gotten a response..i feel like they not even making the effort..i may be wrong..he is a good doctor he explains everything..i just feel like he should knkw what is more effective for my case..i do ovulate on my own..so i feel like taking femara or chlomid is not neccesary..wat yall ladies think..wat should i do? thanks🙌💚