I received a number of Web design proposals for a project I'm working on. Most of the proposals are extraordinarily generic; the only thing that I, as a non-design person can easily distinguish between them is the price.
Is there any advice that industry insiders can recommend that I look for in a proposal--something that I can identify as either being present or conspicuously not present in a proposal that would be either a red flag or a particularly good sign?
I'm writing from a designer's side, but I've also been on the client's side many times, so I would say:
If you have so many to choose from, try to ignore the pricing at first and just choose a couple of options that you think you like for whatever reason. Narrow it down to 2 options that at least stick to your branding and general ideas.
That may be easier said than done, obviously, since you already mentioned they all look kind of generic. Which is not necessarily a problem, since plenty of websites today follow a few very general compositions rules.
Potential green flags: try to look for clues that show a particular provider has at least tried more than others: quality typography and whitespace, consistent formatting, properly aligned elements. Those guys who show a bit of that extra care will probably be the most flexible and understanding when you'll get to request adjustments.
Potential red flags: using outdated software, not being interested in releasing source files, not being interested in making revisions, not presenting responsive options (what the website looks like on a phone).
If there is any illustration involved, try to see if they actually made that, or used stock imagery. Using stock may be restrictive long-term, as you may not always be able to find matching illustration of a specific situation.
Screen these providers by asking tricky questions about either updating the work or creating new designs. Literally say that you don't like it, provide arguments and see their reaction. If something looks like a 10$ template, mention this up front, see what they say.
Be mindful of your budget, as webdesign work can range widely from hundreds to thousands of dollars. If this is a low-budget job, adjust your expectations.
To add to Lucian's answer: Try to short list proposals that actually speak to your need as articulated in your RFP or SOW. If you asked for A (i.e. website or app), a proposal should at least explain how they will do A, before going on at length about their expertise in B (i.e. brand identity).
In my experience, there is no purely algorithmic approach in selecting creative proposals. It is a lot of vetting, short listing, reviewing work samples that match your aesthetic, and Q and A with creatives.