Fortunately, there are a few third-party plugins that can help you curate these strategies with more poweful control. Try out Yith's plugin for product bundles, Woocommerce Products Slider for related product cross-selling, or Checkout Add-Ons to offer upgrade plans to the main product at checkout step.
However, if you ask me whether there is an all-in-one plugin that empowers all 3 upsells, cross-sells and product bundles tactics for WooCommerce, I would recommend Beeketing plugin.
Take a look at how Beeketing plugin can help you create upsells, cross-sells, and product bundles in your WooCommerce store:
The settings is intuitive and easy because the plugin is intent on creating an effortless user experience for even non-tech store owners.
They also gather things up in a real-time updated report of your sales, conversions, and best performing offers so you know where to improve:
My opinions? I like their well-designed popups because they catch attention quickly and highly motivate customers to click the CTA button.
I also like the gamification idea of adding a cart level progress bar that lets customers know how much more they should spend to get a reward discount code:
Feel like you have to give away some discounts to compete with your competitors, though your markup is already too small? Increasing average order value with this small game will help you sell more to each customers, thus generate greater profit per month. Not to mention that you can interact and engage with customers more with this interesting experience.
Remember I mentioned about automated recommendations that WooCommerce's built-in feature doesn't yet support? Beeketing plugin allows you to turn on upsell & cross-sell automation if you don't have time to manually set up offers for all products.
Curious how these recommendations are generated? They built a system of algorithms that analyse all store's sale data and customer behavior patterns (browsing, viewing, adding to cart,...) to generate relevant items that customers most likely want to buy. ConversionXL even pointed out that automated upsells and cross-sells can increase revenue from shopping carts 30-70%. I believe in the power of AI, do you?