Stop right now and ask yourself a question:
Why on earth do your clients hire you instead of the next person?
Really, why do they hire you?
Yes, you might get into a position with a client that just pushes you into bad ideas. Fire the client. If you can’t (sometimes we all just need to pay the bills) then once you’re done, never work for them again.
What if clients don’t value your opinion?
That’s probably your fault. Have you been opinionated on your blog? Were you hired for your opinion or just to push some pixels/code around?
If you're just ‘the WordPress person’ then of course many clients will ignore your opinion. You’re a commodity and commodities (like gas) don’t compete on value, they compete on price, as in who has the lowest one.
I’m not just the guy that can build WordPress sites. I’m the guy that figures out why your site can’t sell it’s $10k software by profiling the site and tracking down that one function that crushes your site.
I’m the guy that builds out custom UI for your users and increases conversions.
I’m the guy that replaces your $50k/year external membership tool that drops connections and thus users.
Yeah I can build a theme and I enjoy doing that, but that’s not why people come to me initially.
The clients you want will be hiring you for your strong opinion. They should be hiring you because you are the expert, not just because you can ‘code’.