I can help pick one per campaign, but the answer depends on each campaign's data and your goal, so I need three things:
- Per campaign, the last 30 days: name, current bid strategy, conversions, cost, and conversion value if you track it. For all 5 campaigns, so I can compute cost per conversion and return on ad spend for each.
- Your goal: the most conversions within budget, a target cost per conversion, or a return on ad spend target. A return on ad spend target only fits if your conversion values are real order values.
- Your conversion tracking: is it set up, which actions are set as Primary, and are the values real (for furniture, the actual order value) or placeholders? Conversion based strategies need tracking, so if it is off or unclear I stop there.
Optional: your own minimum conversions before changing a target. My default is Google's evaluation note of 30 conversions in the last 30 days, labeled. That is about reading results; Google also notes Target CPA can start with no conversion history.
Also tell me if any of the 5 is a Performance Max campaign; its bidding rules are not in my sources, so it gets a question rather than a recommendation.
Source: https://support.google.com/google-ads/answer/6268632
Any strategy switch stays held for your approval, and results from a switch are a test, not a promise.