Venues do require a lot of time and patience in order to rank up (the first levels are the hardest and slowest). I always have my Sims stash some food from home in their inventory (gelatin is quick and works well) or put a mini fridge on the lot, and with a tent or energizer if their aspiration is high enough, they can stay as long as necessary, or as I discovered, use the hobby lot to recharge. Whether that's considered fun or worth it for the player, ymmv. Surprisingly, the higher the rank, the faster it rises despite the substantial increase in loyalty stars required.